A car travels 90 meters due north in 15 seconds. Then the car turns around and travels 40 meters due south in 5 seconds.
What is the magnitude of the average velocity of the car during
this 20 second interval?
C. 6.5
a. 2.5 m/sb. 5.0 m/s
d. 7.0 m/s
m/s

Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past

Calculate the mass of an object that has a momentum of 100kg x m/sec and velocity of 4 m/sec

Unpolarized light falls on two polarizer sheets whose transmission axes are at right angles. a third polarizer is placed between the first two so that its axis makes a 52-degree angle with the axis of the first polarizer. a) what fraction of the incident light intensity is transmitted through the first polaroid? b) what fraction of the incident light intensity is transmitted through the second polaroid? c) what is the angle of polarization of the light that enters the third polaroid? d) what fraction of the incident light intensity is transmitted through the third polaroid. e) what happens if the middle polaroid is removed?