Force, work, energy, power

Front

What is force?

Back

Force is a vector quantity, a push or pull which changes the shape and/or motion of an object. In SI, the unit of force is the newton (N), and in Imperial, it is the pound (lb).

Front

How is weight defined in physics?

Back

Weight is the gravitational force of attraction between a mass and the mass of the Earth. In SI, weight can be calculated as F = mg, where g = 9.81 m/s².

Front

What is Newton's Second Law of Motion?

Back

Newton's Second Law states that an unbalanced force F will cause an object of mass m to accelerate a, according to F = ma.

Front

How is momentum defined?

Back

Momentum is a vector quantity, symbolized as p, and is calculated as p = mv. In SI, the unit is kg m/s.

Front

What is work in physics?

Back

Work is a scalar quantity, equal to the product of a force and the displacement of an object. It is calculated as W = Fs. In SI, the unit of work is the joule (J).

Front

How is energy defined?

Back

Energy is the ability to do work, with units the same as for work: joules (J), kilojoules (kJ), and foot-pounds (ft-lb).

Front

What is kinetic energy?

Back

Kinetic energy is the energy due to motion, calculated as Ek = 1/2 mv². In Imperial, it is expressed as Ek = w/2g v², where w is weight.

Front

What is the formula for kinetic energy of rotation?

Back

The kinetic energy of rotation is calculated as E = 1/2 Iω², where I is the moment of inertia and ω is the angular velocity in rad/s.