C1 Energy Stores And Transfers

Question 1

What is nuclear energy

Answer 1

The amount of energy stored in the nucleus of an atom

Question 2

Define Electrostatic energy

Answer 2

Energy a charged object has when near another object (Repels if same charge, attracts if the opposite charge)

Question 3

Equation for Efficiency (%)

Answer 3

Efficiency (%) = useful power/energy output (Watts/Joules) / Total power/energy input (Watts/Joules)

Question 4

Suggest one way you can reduce energy lost through friction

Answer 4

Lubrication

Question 5

Suggest a way of reducing energy wasted due to air resistance or drag

Answer 5

Streamlining

Question 6

Gravitational potential energy equation

Answer 6

Gravitational potential energy (Joules) = mass (kg) x gravitational field strength (N/kg) x height (m)

Question 7

Equation for kinetic energy

Answer 7

Kinetic energy (joules) = 0.5 x mass (kg) x (velocity)^2 (m/s)

Question 8

Equation for power and time

Answer 8

Power = Energy transfered/work done (joules) / time (seconds)

Question 9

Equation for elastic potential energy

Answer 9

Elastic potential energy (joules) = 0.5 x spring constant (N/m) x (Extension)^2 (m)

Question 10

Why can’t a system have an efficiency of over 100%

Answer 10

Because energy cannot be created or destroyed only dissipated. This means energy input can not exceed the useful power output