Nesseccery An astronaut working on the Moon tries to determine the gravitational constant G by throwing

a Moon rock of mass m with a velocity of v vertically into the sky. The astronaut knows that the

Moon has a density ρ of 3340 kg/m3 and a radius R of 1740 km.

(a) Show with (1) that the potential energy of the rock at height h above the surface is given by:

E = −4πG

3

mρ ·

R3

R + h (2)

(b) Next, show that the gravitational constant can be determined by:

G = 3

8π

v2

ρR2 1 − RR+ h−1 (3)

(c) What is the resulting G if the rock is thrown with 30 km/h and reaches 21.5 m?

If an inclined plane is 5 m long and 2 m high, what is its mechanical advantage? a. 2.5 b. 3 c. 7 d. 10

Using the work energy theorem. what is the velocity of a 850kg car after starting at rest when 13,000j of work is done to it.

A3.9 g aluminum foil ball with a charge of +4.1×10−9 c is suspended on a string in a uniform horizontal e⃗ field. the string deviates to the right and makes an angle of 30∘ with the vertical. part a part complete what information about the e⃗ field can you determine for this situation? what information about the field can you determine for this situation? only the magnitude of e⃗ only the direction of e⃗ both the magnitude and the direction of e⃗ none of the above previous answers correct part b determine the magnitude of the electric field. express your answer with the appropriate units. e e = nothing nothing request answer part c determine the direction of the electric field. determine the direction of the electric field. to the right to the left away from you toward you