List two ways to measure the gravitational potential energy of the ball when it's dropped from different heights

Which statement describes an essential characteristic of data in an experiment?

Motion has occurred when what changes?

Two boats start together and race across a 60-km-wide lake and back. Boat A goes across at 60 km/h and returns at 60 km/h. Boat B goes across at 30 km/h, and its crew, realizing how far behind it is getting, returns at 90 km/h.

List three examples each of objects that are commonly measured by mass by volume and by length

If a ray of light is incident on plane mirror at an angle of 300 its angle of reflection is.

The period of a simple pendulum is 3.8 s. the length of the pendulum is doubled. what is the period t of the longer pendulum? t = s

True or false - sound waves can travel across outer space.

In which one of the following locations can a person hear the echo of a sound? a. At least 33.2 meters behind the reflecting surface b. Less than 16.6 meters in front of the reflecting surface c. Less than 33.2 meters behind the reflecting surface d.

F an electron fell to a lower orbit or energy level, energy would be A. created. B. emitted. C. absorbed. D. transferred.

Which is the correct order from the closest to the sun to the farthest away from the sun? A. terrestrial planets, asteroid belt, gas planets, Kuiper belt B. gas planets, asteroid belt, terrestrial planets, Kuiper belt C.