P1 Energy Flashcards
What are the
energy stores?
1) Magnetic, kinetic, heat (thermal), gravitational, electrostatic, chemical, elastic, electrical, nuclear.
Describe the energy transfers that occur as a ball falls to the ground.
Gravitational potential → kinetic.
3) Give the equation for finding the energy in an object’s kinetic energy store?
3) Ek = 0.5 × m × v2
4) If energy is transferred to an object’s kinetic energy store, what happens to its speed?
4) The speed increases.
5) Give the equation for finding the energy in an object’s gravitational potential energy store.
5) Ep = m × g × h
6) What kind of energy store is energy transferred to when you compress a spring?
6) Elastic potential energy
7) What is the definition of specific heat capacity of a material?
7) How much energy is needed to heat up 1 kg of a material by a temperature of 1˚C.
8) Give the equation that relates energy transferred and specific heat capacity.
8) ΔE= m x c x Δϑ
9) Describe an experiment to find the specific heat capacity of a material.
9) Heater heats a metal block. Balance used to measure mass of block. Joulemeter used to measure amount of energy to block. Thermometer used to measure temp increase of block. Use mass, temperature change and energy to calculate specific heat.
10) State the conservation of energy principle.
10) Energy is never created or destroyed. Only changed from one form to another.
11) Define power and give an equation to calculate power.
11) P = E ÷ t. It is the rate of which energy is transferred.
12) What are the units of power?
12) Watts (W)
13) How can you reduce unwanted energy transfers in a machine with moving, touching components?
13) Use lubricants (like oil)
14) True or false? A high thermal conductivity means there is a high rate of energy transfer.
14) True
15) Give four ways to prevent unwanted energy transfers in a home.
15) Cavity walls, loft insulation, double-glazed windows, draught excluders.
