A girl standing on a floor would have two opposite forces acting on it. These forces are the weight and the normal force. Since no other forces are acting and that the girl is at rest, then the weight must equate to the normal force. Therefore, the supporting force would be:
F = mg = 55kg (9.81 m/s^2) = 539.55 N
Equation: Mass x Velocity = Momentum
Answer: 93 x 13 = 1,209
Answer:
Visible Light
wavelength = 4000 - 7000 Angstroms = 400 - 700 milli-microns
1 A unit = 10^-10 m
1 mμ = 10^-9 m
An object that's moving doesn't necessarily change its speed or acceleration. Also, the force applied to it doesn't need to change ... in fact, a moving object doesn't need ANY force applied to it in order to keep moving.
But any moving object WILL have a change in its position ... THAT's how you know it's moving, and that's WHY you say "It's moving !". (choice-B)