A ball of mass m is moving horizontally with a constant velocity v towards a rigid wall.The wall is moving perpendicular to the direction of motion of ball with a constant speed u. Assuming elastic collision between the ball and rigid wall,the force exerted on the wall by the ball,if impact lasts for 0.1s,is a.20mu b.10mv c.20m(u+v) d.20m√u2+v2
1The answer is
d. 20m√u2+v2
The velocity of the ball can be easily found by equating energy and momenta befor and after the collision.
OR by using the formula derived from the same result
v2=~~~
And then multiplying the then obtained 2m√u2+v2 by 10
[339]
