What is a machine that continues to work without adding additional energy

Which sentences describe star clusters? Check all that apply. Stars appear brighter. Stars form large groupings. Stars form at different times. Stars form from the same nebula. Stars are about the same distance from Earth.

Is the specimen that you brought to school a monocot or dico? Give multiple reasons to explain how you know this

A soap bubble is essentially a thin film of water surrounded by air. The colors you see in soap bubbles are produced by interference.

A train is approaching you at very high speed as you stand next to the tracks. Just as an observer on the train passes you, you both begin to play the same recorded version of a Beethoven symphony on identical MP3 players.

Technician A says that a heater core leak can be the result of the coolant wearing a hole through the core. Technician B says that a core leak can be caused by chemical action eating a hole through the core. Who is correct?

A massive and a less massive object free-fall at the same rate because A. the ratio of the net force to mass is the same for each B. the gravity is the same C. they weigh the same amount D. they experience the same force of gravity E. none

Which of the following lists the Earth's layers in order from hottest to coldest in temperature? A. outer core, mantle, inner core, crust B. crust, mantle, outer core, inner core C. inner core, outer core, mantle, crust D.

A boy does 465 J of work pulling an empty wagon along level ground with a force of 111 N [31o below the horizontal]. A frictional force of 155 N opposes the motion and is actually slowing the wagon down from an initial high velocity.

Which of the following best explains why the tidal bulges on Earth are larger closest to the Moon compared to the tidal bulges closest to the Sun?

an airplane flies with a constant speed of 600 miles per hour. how long will it take to travel a distance of 2100 miles?