Edexcel IGCSE Physics · Spec 6.4-6.5
The Motor Effect: Using the Equation
Worked examples using the motor effect equation (F = BIL).
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The Motor Effect: Using the Equation
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Spec 6.4-6.5
What you need to know
- Use force equals B times I times L
- Rearrange it to find the field, current or length
- Keep the units consistent
Active recall
Quick check
Answer each question before opening the answer.
What is the equation for the force on a current-carrying conductor?
F = B × I × L (force = magnetic flux density × current × length).
What is the force on a 0.5 m wire carrying 2 A in a 3 T field?
F = B × I × L = 3 × 2 × 0.5 = 3 N.
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