What is the main energy source that drives global climate?
a. solar
b. wind
c. mechanical
d. heat

In a system, when potential energy decreases, then entropy also decreases. true false

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?

If an athlete runs once around a track, back to the starting line, her average velocity is zero. true or false?