Find the gravitational force exerted by the earth on a rock of mass 100kg which lies on the surface of the earth. Mass of earth is 6*10^24 kg, radius if the earth is 6.4*10^6 mand G= 6.67*10^-11 SI units.

How does the kinetic energy of a charge change as the charge moves under the effect of an electric field from higher potential to lower potential? a.the kinetic energy increases.b.the kinetic energy decreases.c.the kinetic energy remains the same.d.the kinetic energy is always zero.

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles

The speed of light can be used to measure the