Magnetic force on a moving charge and on a wire
Grade 11 Science Worksheet

Circle the best answer, or write your answer on the line.
A 3 μC bead moves at 400 m/s at 30° to a 0.5 T field. What force acts on it, to 0.01 mN, Bo?
A 4 μC bead moves at 250 m/s at 60° to a 0.8 T field. What force acts on it, to 0.01 mN, Esme?
A 2 μC bead moves at 600 m/s at 20° to a 0.25 T field. What force acts on it, to 0.01 mN, Jun?
Field-line diagram (example data): a uniform field points into the page, drawn as × marks. In the diagram, which way is the force on the electron, Kira?
- Up the page
- Down the page
- Into the page, along the field
In the diagram, which way is the force on the electron, Luz?
Field-line diagram (example data): a uniform field points out of the page, drawn as dots. An electron moves to the right. Field-line diagram (example data): a uniform field points out of the page, drawn as dots. An electron moves to the right. uniform field out of the page e- electron - Up the page
- Down the page
- To the right, along its motion
In the diagram, which way is the force on the electron, Milo?
Field-line diagram (example data): a uniform field points into the page, drawn as × marks. An electron moves up the page. Field-line diagram (example data): a uniform field points into the page, drawn as × marks. An electron moves up the page. - electron - Up the page, along its motion
- To the right
- To the left
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Table (example data), charged beads moving at right angles to a field, with columns bead, charge (μC), speed (m/s) and field (T): A, 2, 100, 0.5; B, 4, 100, 0.5; C, 2, 300, 0.5; D, 2, 100, 1.0.
Using the table, how does bead D's force compare with bead A's, Pia?
- D's force is 4 times A's
- D's force is twice A's
- D's force is half A's
Using the table, which two beads feel equal forces, Ren?
- Beads C and D, at 0.3 mN each
- Beads B and D, at 0.2 mN each
- Beads A and C, at 0.1 mN each
A proton enters a uniform field at right angles to it. What happens to its speed, Tala?
- It decreases until it stops
- It increases as the field pushes it
- It stays the same
What path does a charge follow moving at right angles to a uniform field, by Ari's reading (OpenStax)?
- A straight line along the field
- A straight line that speeds up
- A circle at a steady speed