Magnetic fields & induction worksheet with answers

Free printable Magnetic fields & induction worksheet: 6 problems from easy to exam level, with an answer key. Print it or save it as a PDF.

New worksheetPractise online with hints

For teachers: free to print, copy and use in class. Every new worksheet has new values and its own answer key. A link to ExamProblems on your course page is appreciated.

Name: ____________________   Date: ____________

1.Easy
I = 1.5 AR = 4 cmB = ?

A single circular loop of wire with radius 4 cm carries a current of 1.5 A. Find the magnetic flux density B at its centre.

N = 1I = 1.5 AR = 4 cmμ₀ = 4π × 10⁻⁷ T·m/A
B = µT
2.Easy
nB30°15 cm × 20 cmB = 0.5 T

A rectangular loop of 15 cm by 20 cm lies in a uniform magnetic field of 0.5 T. The field makes an angle of 30° with the normal of the loop. Find the magnetic flux Φ through the loop.

B = 0.5 TA = 15 cm × 20 cm30° to the normal
Φ = mWb
3.Medium
+v = 3 × 10⁶ m/sr = ?B = 0.1 T

A proton moves at 3 × 10⁶ m/s perpendicular to a uniform magnetic field of 0.1 T. Find the radius r of its circular path.

m = 1.673 × 10⁻²⁷ kg|q| = 1.602 × 10⁻¹⁹ Cv = 3 × 10⁶ m/sB = 0.1 T
r = cm
4.Medium
−vBF = ?

An electron moves down the page through a uniform magnetic field pointing out of the page. Click the direction of the magnetic force on it.

v: down the pageB: out of the page
  1. 1up the page
  2. 2to the right
  3. 3down the page
  4. 4to the left
5.Hard
l = 20 cmN = 500, ⌀ 3 cm

A long air-core solenoid has 500 turns, a length of 20 cm and a diameter of 3 cm. Find its self-inductance L.

N = 500l = 20 cm⌀ = 3 cmμ₀ = 4π × 10⁻⁷ T·m/A
L = mH
6.Hard
l = 30 cmN = 400, ⌀ 1 cm

A long air-core solenoid has 400 turns, a length of 30 cm and a diameter of 1 cm. Find its self-inductance L.

N = 400l = 30 cm⌀ = 1 cmμ₀ = 4π × 10⁻⁷ T·m/A
L = µH

Answer key

  1. 1. B = 23.56 µT
  2. 2. Φ = 12.99 mWb
  3. 3. r = 31.33 cm
  4. 4. to the right
  5. 5. L = 1.11 mH
  6. 6. L = 52.64 µH

Full step-by-step solutions: practise this topic on examproblems.com.