P1 : Conservation and dissipation of energy

What is the equation for kinetic energy? Provide SI units.

KE = 1/2 * m * v^2, Units: Energy (J), Mass (kg), Velocity (m/s)

Define 'Specific Heat Capacity'.

Amount of energy needed to raise 1kg of substance by 1°C.

State the units for Specific Heat Capacity.

Units: J/°C/kg or Joules/Degree Celsius/Kilogram.

What is the definition of 'Power'?

Rate at which energy is transferred or work is done.

Give two equations for power with SI units.

Power = energy transferred/time, Power = work done/time. Units: Energy (J), Work Done (J), Time (s)

What is the unit of power?

Watt (W)

Describe energy changes of a thrown ball ignoring air resistance.

KE to GPE upwards, Peak: Max GPE, Zero KE, GPE to KE downwards.

Explain why a bungee jumper slows down when the cord stretches.

KE converted to EPE, KE proportional to (velocity)^2, causing velocity decrease.

Give examples of chemical energy stores.

Food, Fuel (e.g. wood, coal, petrol), Batteries.

Name 4 different energy stores.

1. Kinetic Energy, 2. Gravitational Potential Energy, 3. Elastic Potential Energy, 4. Chemical Energy.