A boy is trying to roll a bowing ball up a hill as shown in the image below. If friction is ignored what is the minimum initial velocity that the ball must have for it to reach the top of the hill? (Recall that g=9.8 m/s^2)
A.14 m/s
B.21 m/s
C.28 m/s
D.7 m/s

An artificial satellite circles the earth in a circular orbit at a location where the acceleration due to gravity is 6.03 m/s^2. determine the orbital period of the satellite.

Which best represents the law of conservation of mass ?

Alinearly polarized electromagnetic wave has an average intensity of 196 w/m^2. this wave is directed towards two ideal polarizers (in real polarizers, transmission is also effected by reflection and absorption). polarizer a is oriented with its transmission axis at an angle of θ_1=20.8∘ with the incident electric field. polarizer b has its axis at an angle of θ_2=63.0∘ with the incident electric field. what is the average intensity of the wave after it passes through polarizer a? what is the average intensity of the wave after it passes through polarizer b? suppose that the two polarizers a and b are interchanged. what would the average intensity be after passing through both polarizers?