# How do you calculate work energy and power in physics?

1. work done = force × distance moved in direction of force.
2. change in gravitational energy = mgh.
3. power = work donetime taken, power = rate of energy transfer.
4. power = force × velocity.
5. efficiency = useful energy transferredtotal work done × 100 %

## What is power physics PDF?

POWER (PHYSICS) In physics, power (symbol: P) is the amount of work done per unit of time. Definition. This can be modeled as an energy flow, equivalent to the rate of change of the energy in a system, or the time rate of doing work, where P is power E is energy W is work t is time.

## How do you calculate work energy?

The amount of energy transferred by a force is called the work done by that force. The formula to find the work done by a particular force on an object is W equals F d cosine theta. W refers to the work done by the force F. In other words, W is telling you the amount of energy that the force F is giving to the object.

## What is the SI unit of work energy and power?

SI unit of work = joule (J) SI unit of energy = joule (J) SI unit of power = watt (W) Dimensional formula of work =ML2T−2.

• P = E t.
• P = W t.
• P = V 2 R.

## What are the three formulas of work?

Work Formula W = Work done. F = Magnitude of the force applied. d = Magnitude of the displacement in the direction of the force. θ = is the angle between the vectors: force and displacement.

## What is the basic formula for work?

To express this concept mathematically, the work W is equal to the force f times the distance d, or W = fd. If the force is being exerted at an angle θ to the displacement, the work done is W = fd cos θ.

## What is the SI unit of work?

The SI unit of work is the joule (J). It is defined as the work done by a force of one newton through a distance of one metre.

## What is the SI unit of energy?

The SI unit of energy is same as that of work, which is joule (J).

## What is Ke formula?

Kinetic energy is directly proportional to the mass of the object and to the square of its velocity: K.E. = 1/2 m v2. If the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

## What is the formula for calculating work in physics?

The formula for calculating work is Work = Force x Distance . Hence, to calculate the distance from force and work, proceed as follows: Determine the work done, W , when the force, F , is applied. Divide the work done, W , by the applied force, F .

## What is the formula of energy in terms of power?

The formula is P = E/t, where P means power, E means energy, and t means time in seconds. This formula states that power is the consumption of energy per unit of time.

## How do you calculate energy in a circuit?

Electrical energy is the product of power multiplied by the length of time it was consumed. So if we know how much power, in Watts is being consumed and the time, in seconds for which it is used, we can find the total energy used in watt-seconds. In other words, Energy = power x time and Power = voltage x current.

## What is dimensional formula of energy?

Energy = m × c2. Or, E = [M] × [L1 T-1]2 = M1 L2 T-2. Therefore, energy is dimensionally represented as M1 L2 T-2.

## What is the difference between calculating power and work?

Work is the energy needed to apply a force to move an object a particular distance. Power is the rate at which that work is done.

## What is Ohm’s law rule?

Ohm’s Law Equation : V = IR, where V is the voltage across the conductor, I is the current flowing through the conductor and R is the resistance provided by the conductor to the flow of current.

## What are the units of power?

We can define power as the rate of doing work, it is the work done in unit time. The SI unit of power is Watt (W) which is joules per second (J/s). Sometimes the power of motor vehicles and other machines is given in terms of Horsepower (hp), which is approximately equal to 745.7 watts.

## How is DC current calculated?

P = V X I . Here P is power in watts. V is voltage in volts. I is current in amps.

## How many formulas are there for work?

The three main equations representing the relationships between energy, work, and force.

## What are the types of work in physics?

Positive, Negative and Zero work done.

## Is work scalar or vector?

Work has only a magnitude but no direction. The formula for work is written as a dot product of force and displacement. Therefore, work is a scalar quantity.

## How is a joule measured?

One joule equals the work done (or energy expended) by a force of one newton (N) acting over a distance of one meter (m). One newton equals a force that produces an acceleration of one meter per second (s) per second on a one kilogram (kg) mass. Therefore, one joule equals one newton•meter.

## What is heat unit?

SI Unit of Heat Generally, all forms of energy are measured in terms of joules in the SI system. Notably, heat is a form of energy, and therefore the SI unit of heat is also joules (J) which are defined as the amount of energy needed to raise the temperature of a given mass by one degree.

## What is the unit of 1 joule?

1 Units. The SI unit for energy is the joule (J): 1 J=1 newton metre (N m). Another unit is the calorie (cal), which is defined as the heat required to raise the temperature of 1 g of pure water by 1°C at 1 atm pressure.