Question

A smooth sphere is moving on a horizontal surface with velocity vector 2i+2j immediately before
it hits a vertical wall. The wall is parallel to j vector and the coefficient of restitution between the sphere and the wall is e=1/2. The velocity vector of the sphere after it hits the wall is
(A) i-j
(B) -i+2j
(C) -i-j
(D) 2i-j​

Answer 1

Answer:

and will be b

Explanation:

just apply simple vector rule and since the wall is parallel to the j vector ..so it will not affect the j vector but will effect all other vectors