A block of mass 0.5 kg is placed over a long plank m of mass 1 kg. The friction coefficient between block and plank is 0.1. The system is placed over a smooth horizontal surface. A time varying force F = 5t Newton starts acting on the block as shown in figure. (g =10 m/s2)
see full answer
Your Exam Success, Personally Taken Care Of
1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.
An Intiative by Sri Chaitanya
a
Block will break off the plank before relative motion starts.
b
Block will break off the plank after the start of relative motion.
c
Relative motion between block and plank starts at t = 15/89 sec.
d
Relative motion between block and plank starts at t = 11/89 sec.
answer is B.
(Unlock A.I Detailed Solution for FREE)
Best Courses for You
JEE
NEET
Foundation JEE
Foundation NEET
CBSE
Detailed Solution
since R= Neff=mg- F Sin370 =0.5×10-5 t ×35R=5-3t For breaking off (R=0)t=5/3secfL=μR=110[5−3t]=12−310t For 0.5kg block, 4t−f=0.5aFor 1kg block,f=1aSolving both, we getf=8t3Relative motion starts when f>fL⇒8t3>12−3t10⇒t>1589s
A block of mass 0.5 kg is placed over a long plank m of mass 1 kg. The friction coefficient between block and plank is 0.1. The system is placed over a smooth horizontal surface. A time varying force F = 5t Newton starts acting on the block as shown in figure. (g =10 m/s2)