physics

• Energy can be transferred between objects by work done, heating or cooling, and electric current.
• The SI unit of energy is the joule (J).
• Work done = force x distance moved in direction of force
• The law of conservation of energy states that the total amount of energy in an isolated system remains constant over time.
• Work is defined as force multiplied by distance moved in the direction of the force.
• Work done = force x distance moved in same direction
• Power is defined as the rate at which work is being done (W/t).
• Power is the rate at which energy is supplied to an object or system.
• Power is the rate at which energy is used or supplied.
• Average power = total energy / time taken
• The formula for power is P = W/t, where P is power, W is work done, and t is time taken to do it.
• The SI unit of power is watt (W), where one watt equals one joule per second.
• Heat transfer occurs when there is a temperature difference between two objects.
• Conduction is heat transfer through direct contact with another object.
• When a force acts on an object to move it through a certain distance, work has been done.
• A negative value for work indicates that energy has been transferred to the object being acted on.
• If no work is done, there must be zero force acting on the object.
• Convection is heat transfer due to movement of hotter particles away from their source.