A certain heat engine extracts 1.30 kJ of heat from a hot temperature reservoir and discharges 0.70 kJ of heat to a cold temperature reservoir. What is the efficiency of this engine?

Would the springs inside a bathroom scale be more compressed or less compressed if you weighed yourself in an elevator that accelerated upward? Accelerated downward?

Which of these expressions are correct variations of the combined gas law? p1v1t2 = p2v2t1 both?

Which statement correctly describes liquid water and water vapor

What will happen if the reverberation time in a big hall is too long? How can we reduce it?

Which receptor cells most directly enable us to distinguish different wavelengths of light?

The train traveled 500 kilometers north to Odessa in 2 hours. What's the train's speed? What is the velocity?

Are microwaves and radio waves faster or slower than other types of electromagnetic energy?

If you dive under-water, you notice an uncomfortable pressure on your eardrums due to the increased pressure. The human eardrum has an area of about 70 mm2 (7*10-5m2), and it can sustain a force of about 7 N without rupturing.

Why cant kinetic energy ever be greater than potential energy

For a stationary observer, when the source of a sound is moving, its pitch appears to change.