Work Energy And Power Question 298
A massive disc of radius R is moved with a constant velocity v on a frictionless table. Another small disc collides with it elastically with a speed of $ v_0= 0.3 m/s $ , the velocities of the discs being parallel. The distance (shown in the figure) is equal to R/2, friction between the discs is negligible. For which u (in m/s) will the small disc move perpendicularly to its original motion after the collision?
Options:
0.1
0.5
1.0
D) 0.01
Show Answer
Answer:
Correct Answer: A
Solution:
$ {V _{0y}}=V_0 sin \theta $ , this component does not change $ v _{0x} = v_0 cos\theta and v_0 cos \theta $
For elastic collision, the relative velocity before collision is equal to the negative of the relative velocity after collision along the $ x $-axis
$ v_0\cos \theta -u\cos\theta =u\cos\theta +v _{x} $
$ Ifv _{x} \cos\theta =v _{0y} \sin\theta $ By solving $ m=0.1 $
BETA
