Explore topic-wise MCQs in Physics Questions and Answers.

This section includes 2 Mcqs, each offering curated multiple-choice questions to sharpen your Physics Questions and Answers knowledge and support exam preparation. Choose a topic below to get started.

1.

A metal rod is forced to move with constant velocity along two parallel metal rails, connected with a strip of metal at one end across a magnetic field (B) of 0.5 T, pointing out of the page. The rod is of length 45 cm and the speed of the rod is 70 cm/s. The rod has a resistance of 10 Ω and the resistance of the rails and connector is negligible. What is the rate at which energy is being transferred to thermal energy?

A. 0.225 W
B. 22.55 W
C. 2.25 × 10-4 W
D. 2.25 × 10-3 W
Answer» E.
Discussion
2.

A bar of length 0.15 m slides along metal rails at a speed of 5 m/s. The bar and rails are in a magnetic field of 40 T, pointing out into the page. The resistance of two resistors in parallel is both 20 Ω, and the resistance of the bar is 5 Ω. What is the current in the bar?

A. 1 A
B. 2 A
C. 3 A
D. 5 A
Answer» C. 3 A
Discussion