Two identical ball bearings in contact with each other and resting on a frictionless table is hit head-on by another ball bearing of the same mass moving initially with a speed V. If the collision is elastic, which of the following figure is a possible result after collision?

Asked by Pragya Singh | 1 year ago |  59

##### Solution :-

The mass of the ball bearing is m

Before the collision, Total K.E. of the system

=$$\dfrac{1}{2}$$mv2 + 0 =$$\dfrac{1}{2}$$ mv2

After the collision, Total K.E. of the system is

Case I, E1 = ($$\dfrac{1}{2}$$) (2m) $$( \dfrac{v}{2})^2$$$$\dfrac{1}{4}$$ mv2

Case II, E2 =( $$\dfrac{1}{2}$$) mv2

Case III, E3 = ($$\dfrac{1}{2}$$) (3m) $$( \dfrac{v}{3})^2$$

=$$\dfrac{3mv^2}{18}=\dfrac{1}{6}mv^2$$

Thus, case II is the only possibility since K.E. is conserved in this case.

Answered by Pragya Singh | 1 year ago

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