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Q: ok im trying to understand something.. but it's really hard for me, so if there's any physics-nerds out there, please help me BUT DON'T USE BIG WORDS! i have a very hard time with physics! k right now im trying to understand a lab we did a few weeks back.. it was like this, we rolled down a ball (on a slide9 and measured where it would land, then we put it lower down on the slide..and it landed closer to the slide.. (obviously) now the point of this lab was for him to explain to us the connection between the height (where on the slide we'd put the ball) and the length (how far away from the slide it would land) but i dont understand! at all! and another thing, he didn't even mention the wieght of the ball! shouldnt that have some affect? like if its heavy it lands further away? (atleast thats what i thought) so if anyone understands this stuff, or know a good website that explains it..PLEASE HELP! my mom would make fun of me if i asked :( so this is my last resort (since ive already written the lab and given it to my teacher it would seem weird if i asked him aboiut it now..cause im supposed to understadn it :P) haha

The higher a ball is from the ground, the greater its potential energy. Since PE (potential energy) = mgh (Mass x force of gravity x height).

When a ball rolls down a slide, the Potential Energy turns into Kinetic energy. KE (kinetic energy) = 1/2(v^2)m (half of the velocity squared times the mass). Assuming that there is no friction, the initial potential energy will be equal to the kinetic energy.

Therfore, mgh=1/2(V^2)m

Due to cross multiplication, the m's cancel. That is why mass is not a factor.

A ball higher up on the slide will reach a greater velocity at the bottom of the slide when it launches off. A greater velocity causes the ball to travel farther. Therefore, a ball with more potential energy will travel farther.

Hope I helped.