Evaluate the magnitude of gravitational force (in N) between two 7 kg spherical steel balls separated by a center-to-center distance of 91 cm.

Hydrogen and helium are both members of?

Explain the comparisons between nature and packingtown that appears on pages 81 and 82 answer

Afisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surface of the water. it takes a time of 2.20 s for the boat to travel from its highest point to its lowest, a total distance of 0.670 m . the fisherman sees that the wave crests are spaced a horizontal distance of 5.80 m apart. (a) how much is the wavelength? (b) find the period of the wave. (c) how fast are the waves traveling? (d) what is the amplitude a of each wave?