A small rock is thrown straight up with initial speed V0 from the edge of the roof of a building with height H. The rock travels upward and then downward to the ground at the base of the building. Let +y be upward, and neglect air resistance. (a) For the rock's motion from the roof to the ground, what is the vertical component Vav-y of its average velocity? Is this quantity positive or negative? Explain. (b) What does your expression for Vav-y give in the limit that H is zero? Explain. (c) Show that your result in part (a) agrees with Eq. (2.10).

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

A17,250 kg rocket is pushed with a thrust of 6,450,284 n. what is the acceleration of the rocket?

Using gravity, an elephant can pull a mouse towards it from the ground. true or false explain why. will give brainliest if answered fast and the best explanation