You shoot a 51-g pebble straight up with a catapult whose spring constant is 320N/m. The catapult is initially stretched by 0.20m. How high above the starting point does the pebble fly? Ignore air resistance.

Answer 1

Elastic potential energy=potential energy
1/2kx^2=mgh
(0.5)(320)(0.2)^2=(0.051)(9.8)h

Solve for h
h=12.8 m