The law of conservation of energy applies:

A. whenever PE = 0.

B. in isolated systems.

C. in all systems

D. only in open mechanical systems.

The atmospheric pressure is due to the (a) sky above our head (b) air mass surrounding the earth (c) gravitational force of sun and other planets. (d) mass of the earth

A molecule is the smallest part of what?

Objects can be accelerating and traveling at constant velocity at the same time. True or False

Andrew pokes a marble, and the marble rolls down a ramp. The marble moves with speed. Which forces are acting on the marble in this situation? When Andrew pokes the marble, he gives it The movement of the marble is slowed down by force.

Which of the following is a consequence of using fossil fuels as an energy source? A. decreased carbon dioxide levels B. increased biodiversity C. increased acid rain D. decreased ecosystem disruption

What is the weight of a 65 kg astronaut on mars?

When lava cools, what type of Rock forms?

A uniformly charged conducting sphere of 1.1 m diameter has a surface charge density of 6.2 µC/m2. (a) Find the net charge on the sphere. (b) What is the total electric flux leaving the surface of the sphere?

A blow-dryer and a vacuum cleaner each operate with a voltage of 120 V. The current rating of the blow-dryer is 12 A, while that of the vacuum cleaner is 5.7 A. Determine the power consumed by (a) the blow-dryer and (b) the vacuum cleaner.

4. A 40 kg child and a 30 kg child want to balance themselves on a 4 meter, 50 kilogramn see-saw. Where should the fulcrum be placed?