Download App

Moving Charges and Magnetism — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsMoving Charges and Magnetism1 Mark
Question
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): An electron and proton enters a magnetic field with equal velocities, then, the force experienced by proton will be more than electron.
Reason (R): The mass of proton is 1999 times more than the mass of electron.
✓

Answer

  1. A is false and R is also false.
Explanation:

The force experienced by a charge particle in a magnetic field is given by,

$\vec{\text{F}}=\text{q}(\vec{\text{v}}\times\vec{\text{B}})$

which is independent of mass. As q, v and Bare same for both the electron and proton, hence both will experience same force.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Assertion (A) & Reason (B) MCQ" from Moving Charges and Magnetism→Moving Charges and Magnetism — all question types→Physics STD 12 Science question papers→Gujarat Board STD 12 Science question papers→Gujarat Board question paper generator→

Similar questions

Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion: Velocity of light is constant in all media.
Reason: Light is an electromagnetic wave which has constant velocity in all media.
→
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion: Light is a transverse wave but not an electromagnetic wave.
Reason: Maxwell showed that speed of electromagnetic waves is related to the permittivity of the medium through which it travels.
→
Two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from thecodes(a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is not the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion: The resistance of p-n junction is low when forward biased and is high when reverse biased.
Reason: In reversed biased, the depletion layer is reduced.
→
For question, statements are given-one labelled Assertion $(A)$ and the other labelled Reason $(R)$. Select the correct answer to these questions from the codes $(a) (b) (c)$ and $(d)$ as given below.
Assertion $(A):$ Nuclear density is extremely higher than atomic density.
Reason $(R):$ Most of the mass of the atom is concentrated in the nucleus.
→
Two statements are given-one labelled Assertion(A) and the other labelled Reason (R). Select the correct answer to these questions from the codes(a), (b), (c) and (d) as given below.
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true but R is NOT the correct explanation of A.
  3. A is true but R is false.
  4. A is false and R is also false.
Assertion (A): A clinic lines on the magnetic map represents lines of equal dip.
Reason (R): When the horizontal and vertical components of the earth's magnetic field are equal, the angle of dip is 60º.
→
Directions: In the following questions, the Assertions (A) and Reason(s) (R) have been put forward. Read both the statements carefully and choose the correct alternative from the following:
Assertion: To protect any instrument from external magnetic field, it is put inside an iron box
Reason: Iron is a ferromagnetic substance
  1. Both A and R are true and R is the correct explanation of A.
  2. Both A and R are true and R is not correct explanation of A.
  3. A is true, But R is false.
  4. A is false, But R is true.
→
For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is NOT the correct explanation of A.
  3. A is true, but R is false.
  4. A is false and R is also false.
Assertion (A): Hydrogen atom consists of only one electron but its emission spectrum has many lines
Reason (R): Only Lyman series is found in the absorption spectrum of hydrogen atom whereas in the emission spectrum, all the series are found.
→
Assertion (A) :A step-up transformer cannot be used as a step-down transformer.
Reason (R): A transformer works only in one direction.
→
Directions: In the following questions, the Assertions (A) and Reason(s) (R) have been put forward. Read both the statements carefully and choose the correct alternative from the following:
Assertion: We cannot think of a magnetic field configuration with three poles.
Reason: A bar magnet does exert a torque on itself due to its own field.
  1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
  2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion.
  3. Assertion is correct but Reason is incorrect.
  4. Both Assertion and Reason are incorrect.
→
For two statements are given-one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $(a), (b), (c)$ and $(d)$ as given below.
Assertion: At resonance, $\text{LCR}$ series circuit have a maximum current.
Reason: At resonance, in $\text{LCR}$ series circuit, the current and e.m.f are in phase with each other.
→