Physics help?

Question

When a car, moving at velocity v, collides with a light volley ball, initially at rest, the ball bounces off with a velocity of approximately? A. (v) B. (2v) C. (1.5v) D. (v/2) E. (-v)

Answer 1

think about it

put some numbers in place of the variables so that you can get the feel of the problem

lets say v is 50 mph (so car is going along a 50 mph) and it hits a volleyball that is at rest (hanging in the air so you can stike it solid with the bumper), what happens

well the ball is clearly going to go the same direction that the car is going (so the -v is out)

now consider the remaining choices v(50 mph), 2v(100 mph), 1.5v(75 mph), and v/2 (25 mph)

even without knowing any physics, it would seem unlikely that the ball velocity would be 1/2 or twice or 1.5 times or whatever

where would that factor come from?

now consider the collision model that you have probably been studying

I hope you are starting to think "a"

Answer 2

The answer is A. (v). Most balls do not have 100% rebound but are pretty close to it. ie if you drop a ball from 3 feet high it will not quite return to 3 feet bouncing back from the floor. However, it is pretty close for the question purposes. Other rubbers would deaden the blow and not have near the velocity but balls do. These are used in shock absorbers and things.

Answer 3

since it says the ball is light, inertia due to mass is negligible and hence the ball will bounce with the same velocity as the car.
answer is A.

Answer 4

lol dude, is this your whole nights homework or somethig? Just Don't give up do ya - an abuse of Yahoo Answers if i ever saw one.

Answer 5

I believe it is A.

Answer 6

helped you once with this topic...you have to learn yourself once in a while. read the book!!!!!!!!!!!!!!!!!!!!!!!!!!