Magnetic field around a wire and inside a coil
Grade 11 Science Worksheet - Building Confidence

Circle the best answer, or write your answer on the line.
A long straight wire carries 6 A. What is the field 3 cm from it, to 0.01 μT, Ari? Use μ₀ = 4π × 10⁻⁷ T·m/A.
A long straight wire carries 1.5 A. What is the field 0.5 cm from it, to 0.01 μT, Bo? Use μ₀ = 4π × 10⁻⁷ T·m/A.
A long straight wire carries 10 A. What is the field 8 cm from it, to 0.01 μT, Kira? Use μ₀ = 4π × 10⁻⁷ T·m/A.
“Field-line diagram (example data):” In the diagram, which way does the field point at P, to the right of the wire, Jun?
- Into the page
- Out of the page
- Straight away from the wire
In the end-on diagram, which way do the field circles run, Milo?
Field-line diagram (example data): a long straight wire carries current out of the page, seen end-on as a dot. Field lines are circles around it, closer together near the wire. Field-line diagram (example data): a long straight wire carries current out of the page, seen end-on as a dot. Field lines are circles around it, closer together near the wire. Field-line diagram (example data) long straight wire current out of the page seen end-on as a dot Field lines - Out from the wire like spokes
- Clockwise, seen from the front
- Counterclockwise, seen from the front
What shape are the field lines around a long straight wire, by Noah's reading (OpenStax)?
- Circles around the wire
- Straight lines pointing away from the wire
- Straight lines parallel to the wire
In the end-on diagram, why are the circles farther apart away from the wire, Pia?
Field-line diagram (example data): a long straight wire carries current out of the page, seen end-on as a dot. Field lines are circles around it, closer together near the wire. Field-line diagram (example data): a long straight wire carries current out of the page, seen end-on as a dot. Field lines are circles around it, closer together near the wire. Field-line diagram (example data) long straight wire current out of the page seen end-on as a dot Field lines - The field weakens as 1 ÷ r
- The field lines point toward the wire
- The current slows down farther out
A compass sits beside a long wire with current. Which way does its needle line up, Ren?
- Pointing straight at the wire
- Along a circle around the wire
- Pointing straight away from the wire
Field-line diagram (example data): a long solenoid of many turns lies left to right. Current runs up the front of each turn. Inside, the field lines are straight, evenly spaced and parallel to the axis; outside, they are far apart. Field-line diagram (example data): a long solenoid of many turns lies left to right. Current runs up the front of each turn. Inside, the field lines are straight, evenly spaced and parallel to the axis; outside, they are far apart. In the solenoid diagram, what is the field like inside, near the middle, Tala?
- Nearly uniform: straight and evenly spaced
- Zero, since the turns cancel
- Strongest near the wire of each turn, weak at the center
In the solenoid diagram, what is the field like outside the solenoid, Zee?
Use the picture in question 9.
- The same as inside
- Stronger than inside
- Nearly zero