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A teacher demonstrated the motor effect - AQA - GCSE Physics Combined Science - Question 4 - 2022 - Paper 2
Question 4
A teacher demonstrated the motor effect. Figure 5 shows the equipment used. Figure 5 Explain why there is a force on the wire when there is a current in the wire.... show full transcript
Worked Solution & Example Answer:A teacher demonstrated the motor effect - AQA - GCSE Physics Combined Science - Question 4 - 2022 - Paper 2
Step 1
Explain why there is a force on the wire when there is a current in the wire.
Answer
There is a magnetic field due to the permanent magnets present in the setup. When an electric current flows through the wire, it produces its own magnetic field. The interaction between the magnetic field of the wire and the magnetic field of the magnets results in a force acting on the wire.
Step 2
Explain how the direction of the force on the wire can be predicted.
Answer
To predict the direction of the force, we can use Fleming's left-hand rule. According to this rule, place your left hand such that the first finger points in the direction of the magnetic field, and the second finger points in the direction of the current. The force on the wire will be in the direction that your thumb points, which is perpendicular to both the current and the magnetic field.
Step 3
Explain one way that the motor could be changed to increase the rate at which the coil rotates.
Answer
To increase the rate at which the coil rotates, you could increase the number of turns of wire in the coil. This would enhance the interaction of the magnetic fields, resulting in a stronger force on the coil. Alternatively, increasing the current in the coil or using a stronger magnet would also achieve this effect.