What is the kinetic energy of an object that has a mass of 30 kilograms and moves with a velocity of 20 m/s?
a. 12,000 j
b. 6,000 j
c. 2,940 j
d. 5,880 j

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

Imagine that someone pushes one marble toward a motionless marble. would there still be action-reaction forces involved in the collision? how might the marbles’ motions be changed? ?

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c