Question

A and B are massless supports attached to two springs, both the springs are identical and light. Friction coefficient between block C and horizontal surface is 0.5.When both the springs are in their natural length block C was given a velocity of 2m/s towards right. Then the distance travelled by block before coming to rest for the first time is

• A. 10cm
• B. 20cm
• C. 15cm
• D. 25 cm
• E. none of these

Answer 1

The correct option is C 15cm

Apply work energy theorem on block C
$\frac{1}{2}k{x}^2+\mu mgx=\frac{1}{2}m{v}_0^2$
The above spring-block arrangement is a parallel combination and thus the equivalent resistance is given as 200 N/m
after substituting the values we get,
$200x^2+20x-8=0$
$x=15cm$