Which refers to the ratio of output force to input force of a machine?

mechanical advantage

average strength

total power

energy requireme

When a star moves away from Earth, its electromagnetic spectrum stretches to make its wavelengths appear longer. Which of these methods makes use of this phenomenon to measure accurately the distance from Earth to a star? a. Doppler Effect b.

A quartz has an index of refraction of 1.46. Diamond has an index of refraction of 2.42. In which material does a light ray entering from air slow down more

A volume of cool air rapidly descends from the top of a mountain. the air is a poor thermal conductor, but its temperature increases as its volume decreases, because of the increase in atmospheric pressure as it reaches the ground.

What is the difference between life and physical science

Which two statements are true about a system? A system is a group of objects analyzed as one unit. Energy that moves across system boundaries is conserved. There's only one way to define the boundaries of a system. All systems are made by humans.

A dc generator is the same as a (n) a. electric motor. b. ac generator. c. armature. d. electric current.

Which of the following best describes scientific knowledge A.) Durable B.) Absolute and never changing C.) Frequently varies

Beth made the chart shown. A 2-column table with 1 row. The first column labeled X has entries Wall clock, T V remote control, Portable music player. The second column labeled Y has entries Refrigerator, Table lamp, Hair dryer.

Which sentence states Newton's third law? If two objects collide, each object exerts a force in the same direction as the other. If two objects collide, each object exerts a force equal to and in the opposite direction of the other.

Why did the chicken cross the road.