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Boss quiz

10 questions on the whole topic. You get one try at each.

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  1. Which energy store fills when a bow is bent?

    • Elastic store
    • Kinetic store
    • Thermal store
    • Chemical store

  2. A roller coaster car rolls down a hill. Which energy transfer takes place?

    • Chemical store to kinetic store
    • Thermal store to kinetic store
    • Gravitational potential store to kinetic store
    • Kinetic store to gravitational potential store

  3. What does the law of conservation of energy say?

    • Energy is destroyed when an object stops
    • Energy is created in power stations
    • Energy disappears as things cool down
    • Energy cannot be created or destroyed

  4. A lamp is supplied with 100 J of energy. It transfers 20 J as light. How much energy is wasted?

    • 80 J
    • 120 J
    • 20 J
    • 100 J

  5. Which unit is used for the energy on a food label?

    • Kilojoules (kJ)
    • Degrees Celsius (°C)
    • Watts (W)
    • Newtons (N)

  6. A 2 kW heater is on for 3 hours. Electricity costs 30p per kWh. What does this cost?

    • £1.80
    • 60p
    • 90p
    • £6.00

  7. Which of these is a renewable energy resource?

    • Crude oil
    • Wind
    • Coal
    • Natural gas

  8. A hot drink is left on a table. Which way is energy transferred?

    • From the hot drink to the cooler room
    • No energy is transferred
    • Both ways equally
    • From the cooler room to the hot drink

  9. How does energy from the Sun reach the Earth?

    • By convection
    • By an electric current
    • By radiation
    • By conduction

  10. Why does a padded coat keep you warm?

    • It is a good conductor
    • It traps air, which is a poor conductor
    • It lets cold air through
    • It makes its own thermal energy
Answers
  1. Elastic store. Stretching, squashing or bending a springy object fills its elastic store.
  2. Gravitational potential store to kinetic store. The car gets lower and faster.
  3. Energy cannot be created or destroyed. Energy is only transferred from one store to another. The total stays the same.
  4. 80 J. 100 J − 20 J = 80 J. The wasted energy heats the surroundings.
  5. Kilojoules (kJ). Food labels list energy in kilojoules. 1 kJ = 1000 J.
  6. £1.80. Cost = 2 kW × 3 h × 30p = 180p, which is £1.80.
  7. Wind. The wind will not run out. The other three are fossil fuels.
  8. From the hot drink to the cooler room. Energy is transferred from hotter to colder, until both are at the same temperature.
  9. By radiation. Space is almost empty. Radiation is the only one of these that needs no particles.
  10. It traps air, which is a poor conductor. The trapped air slows the transfer of energy from your warm body to the cold air.