A 50 kg object traveling at 100 m/s collides (perfectly elastic) with a 50 kg object initially at rest. What is the sum of the momentum of both objects prior to the collision?

a. 100 kgm/s b. 500 kgm/s C. 5,000 kgm/s d. 100,000 kgm/s​

Adding more pulleys to a system of pulleys needed to lift an object. a. increases the force b. decreases the force c. increases the amount of work d. decreases the amount of work

What is the measure of a change in an objects velocity?

The magnitude of the poynting vector of a planar electromagnetic wave has an average value of 0.939 w/m^2 . the wave is incident upon a rectangular area, 1.5 m by 2.0 m, at right angles. how much total electromagnetic energy falls on the area during 1.0 minute?