First slide

Kinetic friction

Question

A block B is pushed momentarily along a horizontal surface with an initial velocity V. If $μ$ is the coefficient of sliding friction between B and the surface, block B will come to rest after a time

Moderate

A

$v / (gμ)$
B

$gμ / V$
C

$g / V$
D

$V / g$

Solution

Friction is the retarding force for the block $F = ma = μmg$
Retardation $a = μg$
From first equation to motion $v = u - at$
$\Rightarrow 0 = V - μg \times t \Rightarrow t = \frac{V}{μ g}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App