physics

• Work done = force x distance moved in direction of force
• Energy can be transferred from one object to another by work done, heating or electrical current.
• The SI unit of energy is the joule (J).
• Power is the rate at which work is done or energy transferred.
• The unit of power is watts (W).
• Energy can be stored, transferred, or transformed from one form to another.
• The energy transfer equation is Energy transferred = Work done + Heat gained/lost + Charge x potential difference
• An open system exchanges both matter and energy with its surroundings.
• A system is an isolated collection of objects that are being considered together as a single entity.
• A system is an area that we are interested in studying, while the surroundings are everything else outside this area.
• A closed system does not exchange matter but may still exchange energy with its surroundings.
• The formula for power is P=W/t where W is work done and t is time taken.
• Average power = total energy / time taken
• An isolated system does not exchange any matter with its surroundings.
• Instantaneous power = work done / time interval
• The SI unit of power is watt (W)
• Average speed = total distance travelled / total time taken
• Instantaneous power = average power if the time intervals are equal
• Kinetic energy is the energy an object has due to its motion.
• Potential energy is the energy that an object has because of its position or state.
• Elastic potential energy is the energy stored when an elastic material is stretched or compressed.
• Work done = Force x distance moved
• Heat gained/lost = Mass x specific heat capacity x temperature change
• Charge x potential difference = Current x charge x potential difference
• Closed systems do not exchange matter but may still exchange energy.
• Isolated systems do not exchange either matter or energy with their surroundings.
• In an isolated system, there is no exchange of either matter or energy between the system and its surroundings.
• Isolated systems neither exchange matter nor energy with their surroundings.
• Thermal equilibrium occurs when two objects are in contact and have equal temperatures.
• Thermal equilibrium occurs when two bodies have equal temperatures.
• When a system interacts with its surroundings, it may gain or lose mass and energy.
• In a closed system, there is no net change in mass over time.
• In a closed system, the total amount of energy remains constant.
• Power can be calculated using the formula P=Energy transferred / Time taken.
• In a closed system, the first law of thermodynamics states that energy cannot be created nor destroyed, only transferred or transformed into different forms.
• Power can be calculated using the equation P=Fvcosθ or P=Fdcosθ
• Work done by a force F acting through distance d at an angle to it is given by W=Fdcosθ.
• Energy is transferred from one place to another by doing work on it.
• When forces act on an object, they cause changes in motion or shape.
• Energy can be transferred between systems by heating or cooling, doing work on them, transferring electrical charge to them, or exchanging radiation with them.