Question

A 25 kg child bounces on a pogo stick.

The pogo stick has a spring with spring constant 2.0*10^4 N/m. When the child makes a nice big bounce, he finds that at the bottom of the bounce he is accelerating upwards at 9.8 m/s^2. How much is the spring compressed?

Answer 1

kx - mg = ma

2*10^4 x = 25 (9.8+9.8)

Answer 2

0.0245

Answer 3

its not .0245

Answer 4

you need to multiply 0.0245 by 100 to convert m to cm to get a final answer of 2.5 cm to two significant figures