no links or i will report. What is the potential energy of stretched spring, if the spring constant is 40 N/m and the elongation is 5 cm?

Acatapult is tested by roman legionnaires. they tabulate the results in a papyrus and 2000 years later the archaeological team reads (distances translated into modern units): range = 0.4 km; angle of launch = π/5 rad; landing height = launch height. what is the initial velocity of launch of the boulders if air resistance is negligible?

What is the mass of the same rock on the earth

What are the applications of electromagnetic waves