What is the equation for calculating a machine's efficiency?

I searched all over my textbook and couldn't find it, so I decided to post my question here.

In a circular loop of wire lying on a horizontal floor, the current is constant and, to a person looking downward, has a clockwise direction. The accompanying magnetic field at the center of the circle is directed a) horizontally and to the east.

A motorcycle has a constant speed of 24.3 m/s as it passes over the top of a hill whose radius of curvature is 182 m. The mass of the motorcycle and driver is 391 kg.

A 1400 kg vehicle travelling at 22 m/s slows at a constant rate to 4.5 m/s in 6.75 s. What was the net force acting on the car during this time?

How is kinetic energy related to the distance

Which compound is an example of a binary ionic compound? A) H2O B) H2SO4 C) MgF2 Eliminate D) SF6

You have two pendulums with cords that are exactly the same length. one is on earth (with an acceleration due to gravity of 9.81 meters/second2) and the other one is on the moon (with an acceleration due to gravity of 1.63 meters/second2).

The magnetic field is 0.0 2M from the wire is 0.1 T what is the magnitude of the magnetic field 0.0 1M from the same wire

A 747 jetliner lands and begins to slow to a stop as it moves along the runway. If its mass is 3.5 x 10 exponent 5 kg, its speed is 27.0 m/s and the net braking force is 4.30 x 10 exponent 5 N, (A) what id its speed 7.

What is matter in context clues

The metallic elements which all react in water are found in the: same group same period rare earth elements