Starting from rest, a 1.9x10-4 kg flea springs straightupward. while the flea is pushing off from the ground, the groundexerts an average upward force of 0.41 n on it. this force does1.8x10-4 j of work on the flea. (a)what is the flea's speed when it leaves the ground? (b) how far upward does the flea move while it ispushing off? ignore both air resistance and the flea's weight.

Molten iron fills a mould, which has a volume of 200 cm cubed. calculate the volume when the iron cools and solidifies. molten iron has a density of 7.0g/cm cubed. in its solid state, iron has a density of 8.0g/cm cubed.

Aregion of space in which a measurable gravitational force is indicated by the force exerted on a test mass is called

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct