Question

A spring with a force constant 400 N/m hangs vertically. You attach a 2.2 kg block to it and allow the mass to fall. What is the max distance the block will fall before it begins moving upward?

Answer 1

The concept: the change in potential energy of the block is EXACTLY equal to the elastic potential energy of the spring. Does that help?

Answer 2

ya a little

Answer 3

i'll get 21.5x = 405x^2 know what?

Answer 4

elastic potential energy is give by 1/2 kx^2. So how can you get 405x^2 ?

Answer 5

*given

Answer 6

* 200 x^2

Answer 7

there you go. So now, all you have to do is... simplify.

Answer 8

that's the part i have trouble with

Answer 9

Just cancel 1 'x' on both sides.

Answer 10

oh ya

Answer 11

so it would be 11 cm?

Answer 12

yep. 10.75 cm.

Answer 13

ok thanks a lot

Answer 14

:)