A battery of emf `2.0 V` and internal resistance `0.10 Omega` is being charged with a current of `5.0 A`. Find the potential difference between the terminals of the battery?

Explanation

We first show velocity components along the t and the n-axis immediately before and after the impact. Angle that the line of impact makes with velocity u is `30^(@)`

Component along t-axis Components of momentum along the t-axis of each disk, considered separately, is conserved. Hence, t-component of velocities of each of the bodies remains unchanged.
`v_(At) = u_(At) = u/2` and `v_(Bt) = u_(Bt)=0 ` ...(i)
The component along the n-axis of the total momentum of the two bodies is conserved
`m_(B)v_(Bn) + m_(A)v_(An) = m_(B)u_(Bn) + m_(A)u_(An) rarr mv_(Bn) + mv_(An) = m xx 0 + m(usqrt3)/2`
`v_(Bn)+v_(An)=(usqrt3)/2` ...(ii)
Concept of coefficient of restitution e is applicable only for the n-component velocities.
`v_(Bn)-V_(An)=e(u_(An)-U_(Bn)) rarr " " v_(Bn)-V_(An)=(usqrt3)/2` ...(iii)
From equations (ii) and (iii), we have `v_(An) = 0` and `v_Bn=(usqrt3)/2` ...(iv)
From equations (i) and(iv) we can write velocities of both the disks.