DC Motors

In this lesson we apply the motor effect to an electric motor to understand how it can rotate.

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 2

Question 2

Question 2

Question 3

Question 3

Question 3

Question 4

Question 4

Question 5

Question 5

Question 5

Question 6

Q1.Match up the quantities in the equation to the correct units shown.

Magnetic flux density

Current

Length

Force

1/5

Q2.A 0.4 m wire with 2 A flowing in it passes through a magnetic field with a magnetic flux density of 0.5 T. What force ix exerted on the wire?

2/5

Q3.For each of the numbers below, how do we convert them ready to use in our equations.

34 mm

650 nT

265 µA

2 km

65 GA

3/5

Q4.A straight wire 0.10 m long carrying a current of 2.0 A is at right angles to a magnetic field. The force on the wire is 0.04 N. What is the strength of the magnetic field?

4/5

Q5.A wire that is 470 mm long hangs at right angles to a magnetic field of 1,800 μT and experiences a force of 9.5 mN. Calculate the current flowing in the wire. (2 s.f)

5/5

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Question 1

Question 2

Question 2

Question 2

Question 2

Question 3

Question 3

Question 3

Question 4

Question 4

Question 5

Question 5

Question 5

Question 6

Q1.Match up the quantities in the equation to the correct units shown.

Magnetic flux density

Current

Length

Force

1/5

Q2.A 0.4 m wire with 2 A flowing in it passes through a magnetic field with a magnetic flux density of 0.5 T. What force ix exerted on the wire?

2/5

Q3.For each of the numbers below, how do we convert them ready to use in our equations.

34 mm

650 nT

265 µA

2 km

65 GA

3/5

Q4.A straight wire 0.10 m long carrying a current of 2.0 A is at right angles to a magnetic field. The force on the wire is 0.04 N. What is the strength of the magnetic field?

4/5

Q5.A wire that is 470 mm long hangs at right angles to a magnetic field of 1,800 μT and experiences a force of 9.5 mN. Calculate the current flowing in the wire. (2 s.f)

5/5

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

DC Motors (HT only)

This quiz will help you consolidate your learning about DC motors.

Question 1

Question 1

Question 2

Question 2

Question 3

Question 3

Question 4

Question 5

Question 5

Question 5

Question 6

Question 6

Q1.Which rule is used to work out the direction of the force exerted on a coil in a motor, when current flows within a magnetic field.

1/6

Q2.What does a force produce when it pushes on something with an axle?

2/6

Q3.Which direction will the force on the wire act?

3/6

Q4.Put the statements below into the correct order.

On one side of the coil the current flows away from us and on the...

… rotate as each force creates a moment.

… produced by the current in the magnetic field will be in opposite ...

The current flows around the coil. The magnetic field is across the coil at right angles to the axis of the coil.

… directions. Because there is a fixed axle, the coil will begin to ...

… other the current flows towards us. This means that the forces ...

4/6

Q5.What is the name of the device that, as the coil spins, makes sure that the moments on the coil always act to spin the coil in the same direction, by swapping over the electrical contact every half turn.

5/6

Q6.Which way will the simple motor shown below rotate? (Hint : use Fleming's Left Hand Rule on one side of the coil)

6/6

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Quiz:

DC Motors (HT only)

This quiz will help you consolidate your learning about DC motors.

Question 1

Question 1

Question 2

Question 2

Question 3

Question 3

Question 4

Question 5

Question 5

Question 5

Question 6

Question 6

Q1.Which rule is used to work out the direction of the force exerted on a coil in a motor, when current flows within a magnetic field.

1/6

Q2.What does a force produce when it pushes on something with an axle?

2/6

Q3.Which direction will the force on the wire act?

3/6

Q4.Put the statements below into the correct order.

On one side of the coil the current flows away from us and on the...

… rotate as each force creates a moment.

… produced by the current in the magnetic field will be in opposite ...

The current flows around the coil. The magnetic field is across the coil at right angles to the axis of the coil.

… directions. Because there is a fixed axle, the coil will begin to ...

… other the current flows towards us. This means that the forces ...

4/6

Q5.What is the name of the device that, as the coil spins, makes sure that the moments on the coil always act to spin the coil in the same direction, by swapping over the electrical contact every half turn.

5/6

Q6.Which way will the simple motor shown below rotate? (Hint : use Fleming's Left Hand Rule on one side of the coil)

6/6

Lesson summary: DC Motors

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