How to Calculate the Velocity and Impact Speed of a Ball Launched by a Spring?

[bmandrade]

Homework Statement

A child's game consists of a block that attaches to a table with a suction cup, a spring connected to that block, a ball, and a launching ramp. The spring has a constant k. the ball has a mass m, and the ramp raises a height h. The spring is compressed a distance S in order to launch the ball. when the ball leaves the launching ramp its velocity makes and angle with respect to the horizontal.

1 Calculate the velocity of the ball when its leaves the launching ramp (both the magnitude and the direction. Be sure to specify your coordinate system)

2. The spring constant = 1000.0 N/m the spring compression is 4. cm the ball's mass is 55 g, the height of the ramp is 15 cm and the top of the table is 1.2 m above the floor. With what speed will the ball hit the floor?

Homework Equations

Delta y = V_ft+1/2gt²
speed=distance/time

The Attempt at a Solution

I really do not have a clue where to start I have been thinking on how to solve it but all i have done is write down some equations that may be helpful but i really don't know if they are helpful in this problem. Can someone please help me? thanks

 

[asleight]

Homework Statement

1 Calculate the velocity of the ball when its leaves the launching ramp (both the magnitude and the direction. Be sure to specify your coordinate system)

2. The spring constant = 1000.0 N/m the spring compression is 4. cm the ball's mass is 55 g, the height of the ramp is 15 cm and the top of the table is 1.2 m above the floor. With what speed will the ball hit the floor?

Have you considered conservation of energy?

 

[bmandrade]

yes i had that equation KEf+PEf=KEi+PEi

so 1/2 mvf² + mgh = 1/2 mvi² + mgh

so in this case masses cancel and i would have to solve for vf

 

[asleight]

yes i had that equation KEf+PEf=KEi+PEi

so 1/2 mvf² + mgh = 1/2 mvi² + mgh

so in this case masses cancel and i would have to solve for vf

Sounds fine by me.

 

[bmandrade]

ok well i know that 1/2mvi^2 = 0 and the mgh final should be 0 too

in that case vf= square root of 2gh

however i got stuck because i there is no value given for h is there a way i can find h or am i suppose to have another equation