A ball of 8.5 kg is thrown upwards 16 meters. What is the gravitational potential energy gained by the ball? Estimate f to 9.81 and keep 4 significant figures.

A150 w lamp emits light of wavelength 590 nm uniformly in all directions. what is the photon flux (photons per unit area per unit time) on a small screen at a distance 2.3 m from the lamp? assume the photons are uniformly distributed over the surface of a sphere of radius 2.3 m.

Free runners jump long distances and land on the ground or a wall. how do they apply newton’s second law to lessen the force of impact?

Which object is most likely represented by a dot?