What Are the Dynamics of Hitting a Helicopter with Tennis Balls in Physics?

[TN17]

Homework Statement

You are sitting on the edge of your school with a tennis ball in your hand. Your friend is doing the same thing sitting on the ground leaning against the wall. You both see a toy helicopter going along the line of the second floor. You both decide to take the helicopter down. You both launch your tennis balls in such a way that you hit the helpcopter at the same time.

a) Where is the helicopter when you launch the ball?
b) Where is the helicopter when your friend launches the ball?
c) What is your friend's initial velcoity?

-School is 10 m high
-Windows are 2 m apart
-g = 10m/s2

I'm assuming that my friend is directly below me.

The Attempt at a Solution

For a) I used delta y = Viy*t + 0.5gt2 to find how long it takes for me to drop the ball. Then, if the helicopter's speed is 2m/0.5s, then it would be 4 m along the second floor line in 1 s, when I drop my ball.

For b) I'm not really sure about. I assumed my friend was directly below and had the same answer for a).

For c), I need help with.

 

[anathema]

Dear fellow forum member,

I would like to provide some input on your questions.

a) When you launch the ball, the helicopter is at a horizontal distance of 4 m along the second floor line, and at a vertical distance of 10 m above the ground (since the school is 10 m high).

b) When your friend launches the ball, the helicopter will still be at the same horizontal distance of 4 m along the second floor line, but its vertical distance will depend on the initial velocity of your friend's ball. If your friend's ball has the same initial velocity as yours, then the helicopter will still be at a vertical distance of 10 m. However, if your friend's ball has a slower initial velocity, the helicopter may have moved slightly downwards by the time the ball reaches it.

c) To find your friend's initial velocity, we can use the equation v = u + at, where v is the final velocity (in this case, 2 m/s), u is the initial velocity (what we want to find), a is the acceleration due to gravity (10 m/s^2) and t is the time it takes for the ball to reach the helicopter. We can use the same time calculated in part a) to find the initial velocity of your friend's ball.

I hope this helps! Let me know if you have any further questions.