Energy changes when charges or magnets move in a field
Grade 11 Science Worksheet
Circle the best answer, or write your answer on the line.
Like charges of 25 nC and 40 nC sit 4 cm apart. With k = 8.9875 × 10⁹ N·m²/C², how much energy is stored, in μJ, to 0.01, Bo?
Like charges of 10 nC and 10 nC sit 2 cm apart. With k = 8.9875 × 10⁹ N·m²/C², how much energy is stored, in μJ, to 0.01, Esme?
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Energy stored by two like charges at different distances (example data)
Distance (cm) Stored energy (μJ) 2 45 4 22.5 8 11.25 16 ? Using the table, what happens to the stored energy each time the distance doubles, Jun?
- It drops to one-quarter
- It halves
- It doubles
Using the table, what energy should be stored at 16 cm, Kira?
- 2.8125 μJ
- 11.25 μJ
- 5.625 μJ
Using the table, the charges are released at 2 cm. What happens, Luz?
- Nothing, since they are at rest
- They pull together
- They fly apart, gaining kinetic energy
A compass needle is turned away from north and let go. Why does it swing back, Noah?
- Its battery turns it
- Air pushes it back
- Field energy turns into its motion
A toy train floats above a track on repelling magnets. What happens to the field energy if the train is pushed down closer, Pia?
- It increases
- It stays the same
- It decreases
An electron is released between a positive and a negative metal plate. What happens to its kinetic energy as it moves, Ren?
- It stays at zero
- It decreases
- It increases
A proton is released near the positive plate. Which way does it move, Tala?
- Toward the negative plate
- Toward the positive plate
- It stays put
As a charge speeds up between the plates, what happens to the stored field energy, Zee?
- It drops by the kinetic energy gained
- It rises by the same amount
- It stays the same
