A wire 0.5 m long carries 2 A at right angles to a magnetic field of 2 T. What force acts on it?
Answer and explanation
Correct answer: A. 2 N
- Step 1: F = BIL sin θ, with sin 90° = 1. Step 2. F = 2 × 2 × 0.5 = 2 N. Answer: 2 N. Why not the others: 4 N is what you get if you forget the length. 0.5 N is what you get if you divide by B. 20 N is what you get if you misplace a power of ten.
Practise more Electricity, Magnetism and Atomic Physics.
Free questions with an explanation for every one, and full timed MDCAT Pakistan mock tests.
More Electricity, Magnetism and Atomic Physics questions
- A 4 μF capacitor is charged to 6 V. How much charge does it store?
- A wire 0.2 m long carries 2 A at right angles to a magnetic field of 0.5 T. What force acts on it?
- A transformer has 100 turns on the primary coil and 2000 turns on the secondary. The primary voltage is 230 V. What is the secondary voltage…
- An object is placed 60 cm from a convex lens of focal length 15 cm. How far from the lens is the image?
- A body moves in a circle of radius 50 m at 10 m/s. What is its centripetal acceleration?
- A stone is dropped from a height of 125 m. How long does it take to reach the ground? (take g = 10 m/s²)