The velocity of an object moving rectilinearly is given as a function of time by v = 4t – 3t 2 , where v is in m/s and t is in seconds. The average velocity of particle between t = 0 to t = 2 seconds is
Two balls are dropped from the top of a high tower with a time interval of t 0 second, where t 0 is smaller than the time taken by the first ball to reach the floor, which is perfectly inelastic. The distance S between the two balls, plotted against the time lapse / from the instant of dropping the second ball, is best represented by
A body is dropped from the top of the tower covers a distance 7h in the last second if its journey, where ‘h’ is the distance covered in the first second. How much time does it take to reach the ground?
The speed of a motor launch with respect to the water is v = 5 ms -1 , the speed of stream u= 3 ms -1 . When the launch began travelled 3.6 km up stream, turned about and caught up with the float. How long is it before the launch reaches the float again? (Find answer in hour).
On a highway, two buses A and B are running at the same velocity of magnitude 30 ms -1 . The brakes caused a deceleration of 30 7 ms − 2 in bus A and that of bus B is 3 ms -2 . In an emergency when driver of the front car applies brakes, immediately its rear light turns red and braking begins. In response, driver of the rear bus also applies brakes to avoid a collision with the front bus. Every driver takes 1 s to apply the brakes after he saw a need for it. If bus A ahead of bus B, then the minimum separation between the buses before driver of bus A applies the brake is x. If bus B is running ahead of bus A, then the minimum separation between the buses before the driver of bus B applies brake is x 2 . The value of x 1 3 x 2 is
Balls A and B are released from rest from roof of a building at t=0 and t=2 s, respectively. The ball A strikes with ground and comes back with same speed. After some time, both balls A and B meet with each other at a height of 55 m from the ground. If the height of building is 60n meter, then the value of n is
A stone is thrown vertically upward. When the stone is at point A, its distance from a certain point O is 6 5 (OA=6 5 ) and the component of velocity along OA is nonzero. When it is at point B(OB= 10 m), the velocity at B is zero. When it is at point C(OC=6 m), the component of velocity of the particle along OC is zero. If the velocity of projection of the stone is v 0 = 5 n ms -1 , then the value of n is
A car accelerates from rest at a constant rate α for some time, after which it decelerates at a constant rate β and comes to rest. If the total time elapsed is t, then the maximum velocity acquired by the car is
A particle moves with uniform acceleration along a straight line AB. Its velocities at A and B are 2 m/s and 14 m/s, respectively. M is the mid-point of AB. The particle takes t 1 seconds to go from A to M and t 2 seconds to go from M to B. Then t 2 /t 1 is
A point moves with uniform acceleration and v 1 , v 2 , and v 3 denote the average velocities in the three successive intervals of time t 1 , t 2 , and t 3 Which of the following relations is correct?
A man swimming downstream overcome a float at a point M. After travelling distance D he turned back and passed the float at a distance of D/2 from the point M, then the ratio of speed of swimmer with respect to still water to the speed of the river will be
From a high tower, at time t = 0, one stone is dropped from rest and simultaneously another stone is projected vertically up with an initial velocity. The graph of distance S between the two stones plotted against time t will be
Each of the three graphs represents acceleration versus time for an object that already has a positive velocity at time t 1 . Which graphs show an object whose speed is increasing for the entire time interval between t 1 and t 2 ?
In travelling a distance of 3 kilometre between points A and D, a car is driven at 100 kmh -1 from A to B for t second and at 60 kmh -1 from C to D for t second. If the brakes are applied for 4 second between B and C to give the car a uniform deceleration, the value of t is
A particle moving in a straight line covers half the distance with Speed V o .The other half of the distance is covered in two equal time intervals with speed V 1 and V 2 respectively. The average speed of the particle during this motion is
A body travels for 15sec starting from rest with a constant acceleration . If it travels distances x, y and z in the first 5 sec,second 5 sec and the next 5 sec respectively. The relation between x, y and z is
From the top of the tower of height 400 m, a ball is dropped by a man, simultaneously from the base of the tower, another ball is thrown up with a velocity 50 m/s; at what distance will they meet from the base of the tower?
A student is standing at a distance of 50 metres from a bus. As soon as the bus begins its motion (starts moving away from student) with an acceleration of 1 ms -2 , the student starts running towards the bus with a uniform velocity u. Assuming the motion to be along a straight road. the minimum value of u, so that the student is able to catch the bus is:
A particle is projected with velocity v 0 along x-axis. The deceleration on the particle is proportional to the square of the distance from the origin i.e., a= α x 2 . The distance at which the particle stops is
A drunkard is walking along a straight road. He takes five steps forward and three steps backward and so on. Each step is 1 m long and takes 1 s. There is a pit on the road 11 m away from the starting point. The drunkard will fall into the pit after
A particle is moving in a straight line. and passes through a point o with a velocity of 6 ms -1 .The particle moves with a constant retardation of 2ms -2 for 4 s and there after moves with constant velocity. How long after leaving O does the particle return to O?
A bus is moving with a velocity 10 ms -1 on a straight road. A scooterist wishes to overtake the bus in 100 s. If the bus is at a distance of 1 km from the scooterist, with what velocity should the scooterist chase the bus?
A particle is thrown up inside a stationary lift of sufficient height. The time off light is T. Now it is thrown again with same initial speed v 0 with respect to lift. At the time of second throw, lift is moving up with speed v 0 and uniform acceleration g upward (the acceleration due to gravity). The new time of flight is
An insect moving along a straight line, travels in every second distance equal to the magnitude of time elapsed. Assuming acceleration to be constant, and the insect starts at t = 0. Find the magnitude of initial velocity of insect
On a highway, two buses A and B are running at the same velocity of magnitude 30 ms -1 . The brakes cause a deceleration or A ms -2 in bus A and that of bus B is 30 7 ms − 2 . In an emergency when driver of the front car applies brakes, immediately its rear light turns red and braking begins. In response, driver of the rear bus also applies brakes to avoid a collision with the front bus. Every driver takes 1 s to apply the brakes after he saw a need for it. If bus A ahead of bus B, then the minimum separation between the buses before driver of bus I applies the brake is x 1 . If bus B is running ahead of bus A, then the minimum separation between the buses before the driver of bus B applies brake is x 2 . The value of x 1 3 x 2 is .
A lift performs the first part of ascent with uniform acceleration a and the remainder with uniform retardation 2a. The lift starts from rest and finally comes to rest. If t is the time of ascent. Find the height ascended by lift.
A truck is moving at a speed of 72 kmh -1 on a straight road. The driver can produce deceleration of 2 ms -2 by applying brakes. The stopping distance of truck is 13x m, if the reaction time of the driver is 0.2 s. The value of x is .
A stone is thrown vertically upward. When the stone is at point A, its distance from a certain point O is 6 5 m at t=0 and the component of velocity along OA is nonzero. When it is at point B(OB=10 m), the component of velocity along OB is zero. When it is at point C (OC=6 m), the component of velocity of the particle along OC is zero. If the velocity of projection of the stone is v 0 = 5 n ms -1 , then the value of n is .
A train is moving on straight track with velocity v 0 = 13.5 ms -1 . To stop the train at a particular station, the driver applies brakes at t = 0, which is caused of a retardation proportional to the velocity of the train. The speed of train reduces 50% in the first 2 s in t 0 =4 . The velocity of train (in ms -1 ) at t=4s (Given , e=2.7)is
A fun drive in an amusement park runs between two spots that are 2.0 km apart. For safety reasons the acceleration of the drive is limited to ± 4.0 m/s 2 , and the jerk, or rate of change of acceleration, is limited to ± 1.0 m/s 2 . The drive has a maximum speed of 144 km/h. If the shortest time taken by the drive to travel between the spots is n 2 , The value of ‘n’ is .
A runner travels around a rectangular track of length 70m and width 30m. After travels around the rectangular track two times, runner back to starting point. Determine distance travelled by the runner.
A body starts from rest and moves with a uniform acceleration of 20 m/s 2 in the first 10s. During the next 10s it moves with the maximum velocity attained uniformly. The total displacement of the body is
A car, starting from rest, is accelerated at a constant rate α until it attains a speed ν . It is then retarded at a constant rate β until it comes to rest. The average speed of the car during its entire journey is
A particle moving in a straight line covers half the distance with speed of 3 ms -1 . The other half of the distance is covered in two equal time intervals with a speeds of 4.5 ms -1 and 7.5 ms -1 respectively. Find the average speed (in m/s) of the particle during this motion
A stone falls from rest. The distance covered by the stone in the last second of its motion equals the distance covered by it during the first three seconds of its motion. How long (in seconds) does the stone take to reach the ground? Take g = 10 ms – 2
Two particles A and B are at separation of 100 m, particle A moves with constant acceleration 4 m / s 2 with initial speed 5m/s and B moves with uniform speed 12m/s, towards each other. When and where the particles meet?
A bullet fired into a fixed target loses half of its velocity after penetrating through a distance 1 cm. How much further distance it will penetrate before coming to rest. (Assuming that it faces constant retardation)
A particle moves in a straight line with a constant acceleration. It changes its velocity from 10 m/s to 20 m/s while passing through a distance of 135 m in time of “t” second. Then value of time “t” is
Two cars A and B are at rest at the origin O. If A starts with a uniform velocity of 20 m/s and B starts in the same direction with a constant acceleration of 2m/ s 2 , then the cars will meet after time
Two trains travelling on the same track are approaching each other with an equal speed of 40 m/s. The drivers of the trains begin to decelerate simultaneously when they are just 2 km apart. Assuming the deceleration to be uniform and equal , the value of the deceleration to barely avoid collision should be …..in m/ s 2
A cyclist starts from rest and moves with a constant acceleration of 1 m/ s 2 . A boy who is 48 m behind the cyclist starts moving with a constant velocity of 10 m/s. After how much time the boy meets the cyclist?
A body” A ” starts from rest with an acceleration a 1 . After 2 sec, another body” B ” starts from rest with an acceleration a 2 . If they cover equal distances in the 5th second after the start of A, then the ratio of a 1 : a 2 is equal to
A particle is moving with constant acceleration from A to B in a straight line AB. If U and V are the velocities of particle at A and B respectively, then its velocity of particle at the midpoint C will be
A particle of mass m is dropped from a height h above the ground. At the same time another particle of the same mass is thrown vertically upwards from the ground with a speed of 2 g h . If they collide head-on completely inelastically, the time taken for the combined mass to reach the ground, in units of h g is :
The distance x covered by a particle in one dimensional motion varies with time t as x 2 = a t 2 + 2 b t + c . If the acceleration of the particle depends on x as x − n , where n is an integer, the value of n is
Train A and train B are running on parallel tracks in the opposite directions with speeds of 36km/hour and 72km/hour respectively. A person is walking in train A in the direction opposite to its motion with a speed of 1.8km/hour. Speed (in m s – 1 ) of this person as observed from train B will be close to: (take the distance between the tracks as negligible)
A Tennis ball is released from a height h and after freely falling on a wooden floor it rebounds and reaches height h 2 . The velocity versus height of the ball during its motion may be represented graphically by : (graph are drawn schematically and on not to scale)
The helicopter rises from rest on the ground vertically upwards with a constant acceleration g . A food packet is dropped from the helicopter when it is at a height h. Time taken by the packet to reach the ground is closed to [ g is the acceleration due to gravity]
A balloon is moving up in air vertically above a point A on the ground . When it is at high h 1 ,a girl standing at a distance d ( point B from A) (see figure) sees it at an angle 45 0 with respect to the vertical . When the balloon climbs up a further height h 2 , it is seen at an angle 60 0 with respect to the vertical if the girl moves further by a distance 2.464d (Point C) . Then the height h 2 is ( Given tan 30 0 =0.5774):
A particle moves from the point 2 i ^ + 4 j ^ m , at t=0 with an initial velocity 5 i ^ + 4 j ^ m / s . It is acted upon by a constant acceleration 4 i ^ + 4 j ^ m / s 2 . What is the distance of the particle from the origin at time t = 2 s in meters?
A police van moving on a high way with a speed of 30km/h fires a bullet at a thief’s car speeding away in the same direction with a speed of 192km/h. If the speed of the bullet with respect to police Van is 150m/s, with what relative speed does the bullet hit the thief’s car?
A truck is moving at a speed of 72 kmh -1 on a straight road. The driver can produce deceleration of 2 ms -2 by applying brakes. The stopping distance of truck is 13x m, if the reaction time of the driver is 0.2 s. The value of x is
On a city road, the last traffic light glows green for 60 s and red for 120 s. The range of speeds of vehicles is from 50 3 ms − 1 to 200 9 ms − 1 in a group. The speed of each vehicle is constant. It is found that at a distance x from traffic light, then the successive groups pushing through traffic light place will become indistinguishable. The value of x (in km) is
A length of path ACB is 1500 m and the length of the path ADB is 2100 m. Two particles start from point A simultaneously around the track ACBDA. One of them travels the track in clockwise sense and other in anticlockwise sense with their respective constant speeds. After 12 s from the start, the first time they meet at the point B. After minimum time (in s) in which they meet first at point B, will they again meet at the point B is time t min = ( 12 ) x s . The value of x is
A thief is running away on a straight road in jeep moving with a speed of 9 ms -1 A police man chases him on a motor cycle moving at a speed of 10 ms -1 . If the instantaneous separation of the jeep from the motorcycle is 100 m, how long will it take for the police to catch the thief
Two trains one of length 100 m and another of length 125 m, are moving in mutually opposite directions along parallel lines, meet each other, each with speed 10 m/s. If their acceleration are 0.3 m/s 2 and 0.2 m/s 2 , respectively, then the time they take to pass each other will be
A body is projected vertically up with a velocity v and after some time it returns to the point from which it was projected. The average velocity and average speed of the body for the total time of flight are
A particle moving in a straight line covers half the distance with speed of 3 m/s. The other half of the distance is covered in two equal time intervals with speed of 4.5 m/s and 7 .5 m/s respectively. The average speed of the particle during this motion is
A ball is dropped vertically from a height d above the ground. It hits the ground and bounces up vertically to a height d/2. Neglecting subsequent motion and air resistance, its velocity y varies with the height h above the ground is correctly shown in
From the top of the tower of height 400 m, & ball is dropped by a man, simultaneously from the base of the tower, another ball is thrown up with a velocity 50 m/s; at what distance will they meet from the base of the tower?
Two trains, which are moving along different tracks in opposite directions, are put on the same track due to a mistake. Their drivers, on noticing the mistake, start slowing down the trains when the trains are 300 m apart. Graphs given below show their velocities as function of time as the trains slow down. The separation between the trains when both have stopped is
Between two stations, a train accelerates from rest uniformly at first, then moves with constant velocity, and finally retards uniformly to come to rest. If the ratio of the time taken is 1:8:1 and the maximum speed attained be 60 km h -1 , then what is the average speed over the whole journey?
A particle starts from the origin with a velocity of 10 m s -1 and moves with a constant acceleration till the velocity increases to 50 ms -1 . At that instant, the acceleration is suddenly reversed. What will be the velocity of the particle, when it returns to the starting point?
The displacement x of a particle moving in one dimension under the action of a constant force is related to time t by the equation t = x + 3 , wherex is in meters and t is in seconds. Find the displacement of the particle when its velocity is zero.
A body starts from rest and travels a distance S with uniform acceleration, then moves uniformly a distance 2S uniformly, and finally comes to rest after moving further 5S under uniform retardation. The ratio of the average velocity to maximum velocity is
A police party is chasing a dacoit in a jeep which is moving at a constant speed v. The dacoit is on a motorcycle. When he is at a distance x from the jeep, he accelerates from rest at a constant rate. Which of the following relations is true if the police is able to catch the dacoit?
The average velocity of a body moving with uniform acceleration after travelling a distance of 3.06 m is 0.34 ms -1 . If the change in velocity of the body is 0.18 ms -1 during this time, its uniform acceleration is
A stone is dropped from the top of a tower of height h. After I s another stone is dropped from the balcony 20 m below the top. Both reach the bottom simultaneously. What is the value of h? Take g=10 ms -2 .
A stone is dropped from a certain height which can reach the ground in 5 s. It is stopped after 3 s of its fall and then it is again released. The total time taken by the stone to reach the ground will be
A ball is thrown from the top of a tower in vertically upward direction. The velocity at a point h meter below the point of projection is twice of the velocity at a point h meter above the point of projection. Find the maximum height reached by the ball above the top of tower.
A juggler keeps on moving four balls in air throwing the balls after regular intervals. When one ball leaves his hand (speed = 20 m s -1 ), the position of other balls (height in meter) will be (take g = 10 ms -2 )
A body is thrown vertically upwards from A, the top of a tower. It reaches the ground in time t 1 . lf it is thrown vertically downwards from A with the same speed, it reaches the ground in time t 2 . If it is allowed to fall freely from A, then the time it takes to reach the ground is given by
A paruchutist drops first freely from an aeroplane for 10 s and then his parachute opens out. Now he descends with a net retardation of 2.5 ms -2 . If he bails out of the plane at a height of 2495 m and g = 10 ms -2 , his velocity on reaching the ground will be
Water drops fall from a tap on the floor 5 m below at regular intervals of time, the first drop striking the floor when the fifth drop begins to fall. The height at which the third drop will be from ground (at the instant when the first drop strikes the ground) will be g = 10 ms − 2
A thief is running away on a straight road in a jeep moving with a speed of 9 ms -1 . A policeman chases him on a motor cycle moving at a speed of 10 m s -1 . If the instantaneous separation of the jeep from the motor cycle is 100 m, how long will it take for the policeman to catch the thief?
A train is moving at a constant speed V when its driver observes another train in front of him on the same track and moving in the same direction with constant speed v. If the distance between the trains is x, then what should be the minimum retardation of the train so as to avoid collision?
A person A is sitting in one train while another person B is in the second train. The trains are moving with velocities 60 m/s and 40 m/s, respectively, in the same direction. Then the velocity of B relative to A will be
Imagine yourself standing in an elevator which is moving with an upward acceleration a = 2 m / s 2 .A coin is dropped from rest from the roof of the elevator, relative to you. The roof to floor height of the elevator is 1.5 m. (Take g = 10 m / s 2 ). rind the velocity of the coin relative to you when it strikes the base of the elevator.
It takes one minute for a passenger standing on an escalator to reach the top. If the escalator does not move it takes him 3 minute to walk up. How long will it take for the passenger to arrive at the top if he walks up the moving escalator?
A bird flies to and fro between two cars which move with velocities v 1 =20 m/s and v 2 =30 m/s. If the speed of the bird is v 3 =10 m/s and the initial distance of separation between them is d=2 km, find the total distance covered by the bird till the cars meet.
The drawing shows velocity (v) versus time (r) graphs for two cyclists moving along the same straight segment of a highway from the same point. The second cyclist starts moving at t = 3 min. At what time do the two cyclists meet?
train normally travels at a uniform speed of 72V,km/h on a long stretch of straight level track. On a particular day, the train was forced to make a 2.0 minute stop at a station along this track. If the train decelerates at a uniform rate of 1.0 m/s 2 and accelerates at a rate of 0.50 m/s 2 , how much time is lost in stopping at the station?
Each of the four particles move along an x-axis. Their coordinates (in metres) as function of time (in seconds) are given by Particle 1: x ( t ) = 3.5 − 2.7 t 3 Particle 2 : x ( t ) = 3.5 + 2.7 t 3 Particle 3: x ( t ) = 3.5 + 2.7 t 2 Particle 4: x ( t ) = 3.5 − 3.4 t − 2.7 t 2 which of these particles is speeding up for t > 0?
When two bodies move uniformly towards each other, the distance between them diminishes by 16 m every 10 s. If bodies move with velocities of the same magnitude and in the same direction as before the distance between then will decrease 3 m every 5 s. The velocity of each body is.
Two objects moving along the same straight line are leaving point A with an acceleration a,2a and velocity 2u, u respectively at time t=0. The distance moved by the object with respect to point A when one object overtakes the other is
Two particles P and Q start from rest and move for equal time on a straight line. Particle P has an acceleration of X m/s 2 for the first half of the total time and 2X m/s 2 for the second half. The particle Q has an acceleration of 2X m/s 2 for the first half of the total time and Xm/s 2 for the second half. Which particle has covered larger distance?
A particle moving along a straight line with a constant acceleration of 4 m/s 2 passes through a point A on the line with a velocity of +8 m/s at some moment. Find the distance travelled by the particle in 5 seconds after that moment.
A stone is dropped from the top of a tower. When it has fallen by 5 m from the top, another stone is dropped from a point 25 m below the top. Ifboth stones reach the ground at the same moment, then height of the tower is (take g = 10 m/s 2 )
Two bikes A and B start from a point. A moves with uniform speed 40 m/s and B starts from rest with uniform acceleration 2 m/s 2 . lf B starts at t =10 and A starts from the same point at t = 10 s, then the time during the journey in which A was ahead of B is
On a city road, the last traffic light glows green for 60 s and red for 120 s. The range of speeds of vehicles is from 50 3 ms − 1 to 200 9 ms − 1 in a group. The speed of each vehicle is constant. It is found that at a distance x from traffic light, then the successive groups pushing through traffic light place will become indistinguishable. The value of x (in km) is .
A length of path ACB is 1500 m and the length of the path ADB is 2100 m. Two particles start from point A simultaneously around the track ACBDA. One of them travels the track in clockwise sense and other in anticlockwise sense with their respective constant speeds. After 12 s from the start, the first time they meet at the point B. After minimum time (in s) in which they meet first at point B, will they again meet at the point t min = ( 12 ) x s . The value of x is .
Balls A and B are released from rest from roof of a building at t = 0 and t = 2 s, respectively. The ball A strikes with ground and comes back with same speed. After some time, both balls A and B meet with each other at a height of 55 m from the ground. If the height of building is 60n metre, then the value of n is .
A ball is thrown vertically upward from the roof of a building with a certain velocity. It reaches the ground in 9 s. When it is thrown downward from the roof with the same initial speed, it takes 4 s to come at ground. How much time (in second) will it take to reach at ground if it just released from the rest from the roof?
A ball is released from rest from top of a tower. The retardation due to air resistance is bv, where b is 10 per second and velocity v is ms -1 . The velocity of ball at t = 1 10 s is n 27 ms − 1 The value of n (Given, e=2.7) is .
The maximum acceleration or deceleration that a train may have is a = 5 ms -2 . The minimum time in which the train may reach from one station to the other separated by a distance d=500 m is t 0 =5 n s. The value of n is .
Two motorboats, which can move with velocities 4.0 m/s and 6.0 m/s relative to water are going up-stream. When the faster one overtakes the slower one, a buoy is dropped from the slower one. After lapse of sometime both the boats turn back simultaneously and move at the same speeds relative to the water as before. Their engines are switched off when they reach the buoy again If the maximum separation between the boats is 200 m after the buoy is dropped and water flow velocity is 1.5 m/s, find the distance between the two places where the boats meet the buoy is found to be 100 × n meters, the value of ‘n’ is .
An object falls from a bridge that is 45m above the water. It falls directly into a small row-boat moving with constant velocity that was 12m from the point of impact when the object was released. What was the speed of the boat?
A body starts from rest and travels with a uniform acceleration of 5 m / s 2 and then decelerates at a uniform rate of 3 m / s 2 again to come to rest. Total time of travel is 10s . Then the maximum velocity attained by the body is
A helicopter is flying horizontally at 8 m/s at an altitude 180 m when a package of emergency medical supplies is ejected horizontally backward with a speed of 12 m/s relative to the helicopter. Ignoring air resistance, what is the horizontal distance between the package and the helicopter when the package hits the ground?
A very broad elevator plateform is going up vertically with a constant acceleration 1 ms -2 . At the instant when the velocity of the lift is 2 m/s, a stone is projected from the plateform with a speed of 20 m/s relative to the floor at an elevation 30 o . The time taken by the stone to return to the floor will be
A car is moving at a certain speed. The minimum distance over which it can be stopped is x. If the speed of the car is doubled, what will be the minimum distance over which the car can be stopped for the same retardation?
A parachutist drops freely from an airplane for 10 s before the parachute opens. He then descends with a uniform retardation of 2.5 ms -2 . If he bails out of the plane at a height of 2495 m and g is 10 ms -2 , his velocity on reaching the ground will be
A particle moving in a straight line covers half the distance with a speed of 3 m/s. The other half of the distance is covered in two equal time intervals with speeds of 4.5 m/s and 7.5 m/s respectively. The average speed (in m/s) of the particle during this motion is
A body, moving in a straight line with an initial velocity of 5 ms -1 and a constant acceleration, covers a distance of 30 m in the 3 rd second. How much distance (in m) will it cover in the next 2 seconds?
Velocity of a particle moving in a straight line varies with its displacement as v = ( 4 + 4 s ) m / s . Displacement of a particle at time t = 0 i s s = 0 . Find displacement of particle at time t = 2 s .
From ground a balloon starts ascending at a constant speed of 25 m/s. After 5 sec a bullet is shot vertically upward from the ground. Find the minimum speed of bullet at which it is able to hit the balloon.
A police jeep is chasing a culprit going on a motorbike. The motorbike crosses a turning at a speed of 72 km h -1 . The jeep follows it at a speed of 90 km h -1 , crossing the turning 10 s later than the bike. The distance (in km) from turning point at which the police catch the culprit is .
A person walks up a stalled 15 m long escalator in 90 s . When standing on the same escalator now moving, the person is carried up in 60 s . How much time would it take that person to walk up the moving escalator? . Does the answer depend on the length of the escalator?
The retardation experienced by a moving motor boat, after its engine is cut-off, is given by dv dt = – kv 3 where k is a constant. If v 0 is the magnitude of the velocity at cut-off, the magnitude of the velocity at time t after the cut-off is