To measure the height of a building without a ruler or tape measure, an engineer drops a rock off the top of the building and finds out it takes 4.9 seconds for the rock to reach the ground. how high is the building could you tell me the steps, as well? i kind of understand how to do it, but some would be greatly appreciated (: .

The relevant equation we can use in this problem is:

h = v0 t + 0.5 g t^2

where h is height, v0 is initial velocity, t is time, g is gravity

Since it was stated that the rock was drop, so it was free fall and v0 = 0, therefore:

h = 0 + 0.5 * 9.81 m/s^2 * (4.9 s)^2

h = 117.77 m

a.) travels faster in solids because the particles are closer together.

air is a gas water is a liquid

the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it