the useful power out of an electric motor is 20w and the total power into the motor is 80w calculate the percentage efficiency of the motor

The world speed record on water was set on October 18,1978 by Ken Warby. If ken drove his motorboat a distance of 1500m in 3,1023, how fast was his boat moving in meters per second and kilometers per hour?

Which statement about the spectrum of light that emerges from a prism is true? A. High-frequency colors bend more than low-frequency colors. B. High-frequency colors bend less than low-frequency colors. C.

A rifle fires a 2.90 x 10-2-kg pellet straight upward, because the pellet rests on a compressed spring that is released when the trigger is pulled. The spring has a negligible mass and is compressed by 8.37 x 10-2 m from its unstrained length.

A gas occupies 210 ml at - 73c. To have the same gas occupy 360ml, should the temperature be increased or decreased

A patient needs to take 375 mg of ibuprofen twice daily. The pills in the bottle are each 250. mg. How many pills does the patient need to take each time she wants the 375 mg dosage?

A crude approximation for the x component of velocity in an incompressible laminar boundary layer is a linear variation from u = 0 at the surface (y = 0) to the freestream velocity, U, at the boundary-layer edge (y = δ).

Why did dad leave mom?

Sal drew the electron dot diagram of an aluminum atom as shown. How should Sal correct his diagram? He should add five more dots so that the atom obeys the octet rule. He should add ten more dots so that all thirteen electrons are shown.

What uses electricity

How do the elements in the Noble Gas family compare?