If a system requires 150 j of input work and produces 123 J of output work, whats its effiency

The law of conservation of energy states that momentum is conserved in a collision. true or false

If total (PE + KE) is considered

What are the five plants you can see from earth without a telescope?

Suppose that you drop a marble from the top of a building, which is about 830m tall. If you ignore air resistance, how long will it take for the marble to hit the ground?

A car travelling at 15 m/s increases it's speed to 20 m/s in 10 seconds. its average acceleration is?

Which is a branch of Earth science? physics ecology chemistry geology

A 6,600 kg train car moving at + 2.0 m/s bumps into and locks together with one of mass 5,400 kg moving at - 3.0 m/s. What is their final velocity? A.) - 1.0 m/s B.) + 2.5 m/s C.) - 0.25 m/s D.) + 0.50 m/s

Why does matter absorb sound energy?

What is the speed of a wave if the wave length is 100 m and the period is 20 s? A. 80 m/s B. 120 m/s C. 2,000 m/s D. 5 m/s

Which best explains why magnets can push on or pull other magnets without touching them? North poles always attract each other, and south poles always force each other away.