Why are all machines not 100% efficient

A. Mass

B. Gravity

C. Friction

D. Distance

Which type of heat transfer can happen through empty space? which type of heat transfer can happen through empty space? radiation conduction convection evaporation?

A stone is dropped from the edge of a roof. find the distance travelled by the stone in 2sec after its release.

A 2,000-kg car moving east at 10.0 m/s collides with a 3,000-kg car moving north. The cars stick together and move as a unit after the collision, at an angle of 48.0° north of east and at a speed of 5.98 m/s.

The half-life of hydrogen-3 is 12.3 years. Given 100 g of hydrogen-3, how many grams will be left after 5 half-lives?

A diver leaves the springboard with a vertical velocity of 5.7 m/s, a horizontal velocity of 1.2 m/s, and a height of 3.49 m. How long will it take her to return to the same height

Lightning heats the surrounding air to

Is a broom an example of a wedge?

Use your knowledge of the state of matter and the other physical properties of matter to write an explanation for what may have caused the following situation: Although it hasn't rained in a week, every morning the grass and the car windows are wet.

What is three example of technology

Lisa has three classes that each last 50 minutes qhat ia the total nuber of minutes of minutes of the three classe?