Quantum Physics Questions

Two main branches of physics are classical physics and quantum physics.

Quantum mechanics is a branch of physics that deals with the behaviour of matter and light on the atomic and subatomic scales. Classical Physics could not explain the dual behaviour of matter and Heisenberg’s uncertainty principle. Quantum physics was successful in explaining the dual behaviour of matter.

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Important Quantum Physics Questions with Answers

1. Does classical physics explain the dual behaviour of matter?

No, classical physics was not successful in explaining the dual behaviour of matter.

2. Choose the correct answer: Which among the following could explain Heisenberg’s uncertainty principle.

  1. Classical physics
  2. Quantum physics

Answer: b) Quantum physics

Explanation: Quantum physics was able to explain Heisenberg’s uncertainty principle.

3. Heisenberg’s uncertainty principle is also known as ______

  1. Indeterminacy principle
  2. Uncertainty principle
  3. Unpredictable principle
  4. Option a) and b)

Answer: d) Option a) and b)

Explanation: Heisenberg’s uncertainty principle is also referred to as the indeterminacy principle of the uncertainty principle.

4. Who proposed the uncertainty principle?

In 1927, Werner Heisenberg, the German physicist, proposed Heisenberg’s uncertainty principle.

5. The De-Broglie relationship is given by ______

  1. \(\begin{array}{l}λ = \frac {h}{mv}\end{array} \)
  2. \(\begin{array}{l}λ = {h}+{mv}\end{array} \)
  3. \(\begin{array}{l}λ = {h}-{mv}\end{array} \)
  4. \(\begin{array}{l}λ = h+m+v\end{array} \)

Answer: a)

\(\begin{array}{l}λ = \frac {h}{mv}\end{array} \)

Explanation: The De-Broglie equation which gives the relationship between matter-waves is given by,

\(\begin{array}{l}λ = \frac {h}{mv}\end{array} \)

6. What is meant by the dual behaviour of particles?

The dual behaviour of particles refers to the ability of the particles to display particle and wave nature.

7. Choose the correct answer: Which field considers the dual behaviour of matter.

  1. Classical physics
  2. Quantum physics

Answer: b) Quantum physics

Explanation: Quantum physics

8. The momentum of a particle is equal to the product of _____ and _____.

  1. Mass, weight
  2. Mass, velocity
  3. Mass, acceleration
  4. Mass, force

Answer: b) Mass, velocity

Explanation: Momentum is defined as the product of mass and velocity.

9. According to the quantum mechanics, the photoelectric equation is given by _____

  1. Kmax = hf + Φ
  2. Kmax = hf – Φ
  3. Kmax = hf × Φ
  4. Kmax = hf/Φ

Answer: b) Kmax = hf – Φ

Explanation: The photoelectric equation as per quantum mechanics is given by Kmax = hf – Φ.

10. Who coined the term quantum mechanics?

Quantum mechanics was coined in early 1920 by Wolfgang Pauli, Werner Heisenberg, and Max Born.

Watch the video to see the standing wave in action.

Practice Questions

  1. Define physics.
  2. What is meant by classical physics?
  3. Explain the dual nature of light.
  4. Explain the De-Broglie relationship.
  5. What is thermodynamics?

Related links

Hertz And Lenard’s Observations Of The Photoelectric Effect

Thermodynamics

De-Broglie’s equation

Magnetic field