You and two friends apply a force of 425 N to push a piano up a 2.0 m long ramp. If lifting the piano straight up requires 1700 N of force, what is the mechanical advantage of the ramp?

You are designing a lathe motor, part of which consists of a uniform cylinder whose mass is 130 kg and whose radius is 0.40 m that is mounted so that it turns without friction on its axis, which is fixed.

A 50.0-kg skater begins a spin with an angular speed of 4.0 rad/s. By changing the position of her arms, the skater decreases her moment of inertia to one-half its initial value. What is the skater's final angular speed?

How to find the number of moles from molar mass?

What kind of charged particle was transferred between the rod and the sphere?

What energy change would accompany the loss of 0.1 mg in mass? Express the energy change in kilojoules to one significant digit.

Tired of being chased by a jaguar, you set a trap. Hoping to drop it on the jaguar, you try to push a 44.0 kg stone boulder off of the edge of a cliff that slopes down at an angle of 15.0°.

Why do stars appear to move through the night sky at the rate of 15 degrees per hour?

What is a Ramjet engine?

An airplane started at a distance of 20 km from Chicago and flew directly away from it. 10 minutes later, the airplane was 55 km from Chicago. If dis the distance of the airplane from Chicago, what is Ad? A. 10 km B. 55 km C. 35 km D. 20 km

An alpha particle travels at a velocity of magnitude 550 m/s through a uniform magnetic field of magnitude 0.045T. (An alpha particle has a charge of charge of + 3.2 x 10-19 C and a mass 6.