Physics: Work and Energy

Study Notes

Definition: Work is the transfer of energy from one object to another due to a force applied over a distance.
Formula: W = F × d (Work = Force × Distance)
Units: Joules (J)
Types of work:
1. Positive work: Force and displacement are in the same direction.
2. Negative work: Force and displacement are in opposite directions.

Definition: Energy is the ability to do work.
Types of energy:
1. Kinetic energy: Energy of motion (Ek = 0.5 × m × v²)
2. Potential energy: Energy of position or stored energy (Ep = m × g × h)
3. Thermal energy: Energy of heat
4. Electrical energy: Energy associated with moving charges
Units: Joules (J)

Definition: Power is the rate at which work is done or energy is transferred.
Formula: P = W / t (Power = Work / Time)
Units: Watts (W)
Types of power:
1. Mechanical power: Power associated with mechanical systems
2. Electrical power: Power associated with electrical systems

Conservation of energy: Energy cannot be created or destroyed, only converted from one form to another.
Work-energy theorem: The net work done on an object is equal to its change in kinetic energy.

Work is the transfer of energy from one object to another due to a force applied over a distance.
Work is calculated using the formula W = F × d, where F is the force and d is the distance.
Work is measured in Joules (J).
There are two types of work: positive work, where the force and displacement are in the same direction, and negative work, where the force and displacement are in opposite directions.

Energy is the ability to do work.
Energy is classified into four types: kinetic energy, potential energy, thermal energy, and electrical energy.
Kinetic energy is the energy of motion, calculated using the formula Ek = 0.5 × m × v², where m is the mass and v is the velocity.
Potential energy is the energy of position or stored energy, calculated using the formula Ep = m × g × h, where m is the mass, g is the acceleration due to gravity, and h is the height.
Thermal energy is the energy of heat.
Electrical energy is the energy associated with moving charges.
Energy is measured in Joules (J).

Power is the rate at which work is done or energy is transferred.
Power is calculated using the formula P = W / t, where W is the work and t is the time.
Power is measured in Watts (W).
There are two types of power: mechanical power, associated with mechanical systems, and electrical power, associated with electrical systems.

The law of conservation of energy states that energy cannot be created or destroyed, only converted from one form to another.
The work-energy theorem states that the net work done on an object is equal to its change in kinetic energy.