Spring launcher firing steel balls

[carmenmaki]

Homework Statement

A small spring-loaded launcher is designed to fire steel ball bearings with masses of 0.22 kg. When setting the launcher, you compress the spring a distance of 15 cm. You then fire the launcher straight up and find that the projectiles reach a maximum height of 0.9 m above the point that they leave the launcher. You load another ball bearing, compress the spring a distance of 20 cm, and place it horizontally at the edge of a table that is 0.5 m
tall.
You fire the ball from the edge of the table. How far from the base of the table does it hit the ground?

Relevant Equations

PE = 1/2 Kx^2
KE = 1/2 mv^2

i have no idea

 

[erobz]

Homework Statement: A small spring-loaded launcher is designed to fire steel ball bearings with masses of 0.22 kg. When setting the launcher, you compress the spring a distance of 15 cm. You then fire the launcher straight up and find that the projectiles reach a maximum height of 0.9 m above the point that they leave the launcher. You load another ball bearing, compress the spring a distance of 20 cm, and place it horizontally at the edge of a table that is 0.5 m
tall.
You fire the ball from the edge of the table. How far from the base of the table does it hit the ground?
Relevant Equations: PE = 1/2 Kx^2
KE = 1/2 mv^2

i have no idea

"I have no idea" doesn't work here. You must give a reasonable attempt to show that you have and/or are thinking about it.

Start with what you do know, or even an outline/diagram of what you think you have to figure out. “Drawing it out” is usually of some good value in the problem solving strategy.

 

[Nugatory]

i have no idea

That just means that your first step is to get an idea. They wouldn’t have assigned you this problem if it didn’t have something to do with the material you’ve been asked to study, so go back and look at that. “You compress the spring a distance of 15cm”…. Somewhere in that material you’ll see how to relate a force applied over a distance to energy…. And you already have the kinetic and potential energy equations… and you know that energy is conserved so once the ball is in the air its total energy is conserved…. Can you calculate the speed and height of the balls as a function of time?

You can do this. And if you try and find yourself stuck we can help you get unstuck, but you have to try.