P1 Energy Flashcards
Name all the 8 energy stores.
Chemical, Nuclear, Elastic, Thermal, Kinetic, Magnetic, Gravitational Potential, Electrostatic
What is gravitational potential energy?
Energy stored in an object due to its height above the ground.
What is elastic potential energy?
Energy stored when an object is stretched or compressed, like a spring.
What is chemical energy?
Energy stored in chemical bonds, such as in food, fuels, or batteries.
What is kinetic energy?
Energy an object has due to its motion.
What is nuclear energy?
Energy stored in the nucleus of an atom, released during nuclear reactions.
What happens to energy in a closed system?
Energy is conserved; it cannot be created or destroyed, only transferred or transformed.
What is the equation for kinetic energy?
Kinetic Energy (J) = 0.5 × mass (kg) × velocity² (m/s²).
What is the equation for gravitational potential energy?
Gravitational Potential Energy (J) = mass (kg) × gravitational field strength (N/kg) × height (m).
What happens to energy in a system when a car accelerates?
Chemical energy in the fuel is converted into kinetic energy.
How is energy transferred in a mechanical system?
Through forces doing work, causing energy to be transferred from one store to another.
What is the relationship between work done and energy transfer?
Work done is the transfer of energy from one store to another.
What is power in terms of energy transfer?
Power is the rate at which energy is transferred or work is done.
What is the unit of power?
The watt (W), where 1 watt equals 1 joule per second (J/s).
What is Specific Heat Capacity?
The specific heat capacity of a substance is the amount of energy required to raise the temperature of 1kg of the substance by 1°C.
How do you calculate specific heat capacity?
specific heat capacity (J/kg°C) = change in energy (J) / mass (kg) x temperature change (°C)
How do we calculate efficiency?
Useful output energy transfer / Total input energy transfer
What is efficiency?
Efficiency is the ratio of useful energy output to total energy input, usually expressed as a percentage.
Suggest a method to determine the specific heat capacity of oil.
Set up the apparatus: Pour a known mass of oil into a beaker. Place the beaker in an insulated container (e.g., a calorimeter) with insulating foam around it to minimize heat loss.
Insert a thermometer and heater: Place a thermometer into the oil to measure temperature and insert a known-power electric heater into the oil.
Measure the initial temperature: Record the initial temperature of the oil before turning on the heater.
Switch on the heater: Turn on the heater and allow it to heat the oil for a set period, typically around 30 minutes, while making sure the heater is submerged in the oil.
Measure the final temperature: After 30 minutes, record the final temperature of the oil using the thermometer.
Calculate the specific heat capacity. Using change in energy / mass x change in temperature
What are possible inaccuracies of the specific heat capacity practical?
- Not all thermal energy is going into the beaker (Fully submerge the heater)
- Incorrectly reading the thermometer (Use electronic temperature probe.)
- Thermal energy may not be spread (Stir the oil.)
