The speed of light in vacuum is approximately MCQ with Answer and Explanation

Question

Share Report Error

The speed of light in vacuum is approximately

A. 3 × 10⁶ km/s

B. 3 × 10⁴ m/s

C. 3 × 10⁵ m/s

D. 3 × 10⁸ m/s

Answer: Option D

Solution (By JKExamLibrary)

3×10⁸ m/s = 3×10⁵ km/s.

This question belongs to: Science Physics

Request complete Subject PDF

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Physics Questions

Question #1

Share Report

In an electric circuit, ammeter is connected in

A. Series

B. Parallel

C. Either

D. Across load

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option A

Explanation:
Ammeter must be in series to measure full current. Very low internal resistance.

This question belongs to: Science Physics

Question #2

Share Report

The speed of sound in air at 20°C is approximately

A. 360 m/s

B. 300 m/s

C. 343 m/s

D. 330 m/s

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option C

Explanation:
At 0°C ≈ 331 m/s, increases with temperature. At 20°C ≈ 343 m/s.

This question belongs to: Science Physics

Question #3

Share Report

A bullet of mass 10 g moving at 300 m/s penetrates 10 cm into a wooden block. Average resistive force is

A. 9000 N

B. 1500 N

C. 3000 N

D. 4500 N

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option D

Explanation:
KE lost = ½ m v² = ½×0.01×90000 = 450 J. Work = F×s => 450 = F×0.1 => F = 4500 N.

This question belongs to: Science Physics

Explore All Physics MCQs