Reflecting telescopes are popular because they're

A. more powerful than a refracting telescope.

B. smaller than a refracting telescope.

C. easier to build than a refracting telescope.

D. more durable than a refracting telescope.

The first scientist to show that atoms emit any negative particles was

The size of a force vector shows; A. the direction of the force B. the magnitude of the force C. the length the object will move because of the force D. the acceleration of the object

The water that powers the generators enters and leaves the system at a low speed (thus we can neglect its change of kinetic energy) and loses 160 m of altitude during the process.

Which of the following is not an appropriate unit for momentum? g*m/s kg*m/hr km*m/s g*cm/min

During an investigation a scientist heated 27 g of mercuric oxide till it decomposed to leave a dry product. The total mass of the product formed was 25 g.

Choose all the answers that apply. The sun: - is the largest star in our solar system - is the largest star in our galaxy - is made mostly of hydrogen and helium -will eventually run out of fuel and die -creates energy through nuclear reactions

Calculate the kinetic energy of a truck that has a mass of 2900kg and is moving at 55m/s.

In the calorimetry experiment which energy will be calculated during the heat exchange if water is used?

A turtle, moving at a constant velocity of 0.9 m/s due south, is in a race with a rabbit, who runs at a moderate speed of 9 m/s.

What might cause a theory to change over time?