Question # 1 : It a particle increases its speed by a factor of 2, what happens to the kinetic energy?

a)doubles
b)cuts in half
c)increases by a factor of 4
d)depends on whether or not work is done on the particle

Question # 2: An object falling near the surface of the Earth
a)decreases its potential energy due to gravity
b)has positive work done on it by gravity
c)both a and b
d)either a or b, depending on whether or not the Earth and the object or just the object are the system.

compare (1/2) m v^2 to (1/2) m (2 v)^2

the second is 4 times the first

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a) is correct
b) is correct
so c)