Download App

Model Paper 7 — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceModel Paper 71 Mark
MCQ
Assertion (A): The atoms of different elements having same mass number but different atomic numbers are known as isobars.
Reason (R): The sum of protons and neutrons, in the isobars is always different.
  • A
    Both A and R are true and R is the correct explanation of A
  • B
    Both A and R are true but R is not the correct explanation of A.
  • ✓
    A is true but R is false.
  • D
    $A$ is false but $R$ is true.
✓

Answer

Correct option: C.
A is true but R is false.
(c) A is true but R is false.
Explanation: Sum of protons and neutrons is known as mass number which is same for isobars.

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 Model Paper 7→Model Paper 7 — all question types→Science STD 9 question papers→Gujarat Board STD 9 question papers→Gujarat Board question paper generator→

Similar questions

A statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as Mark the correct choice as: Assertion: Work done by a body is zero only when, displacement produced by the force is zero.
Reason: Work done by a force is negative when, displacement occurs in the direction of applied force.
→
In each of the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as:
Assertion: Water hyacinth can float on water surface.
Reason: Aerenchyma tissue is present in water hyacinth.
→
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: The slope of distance time graph gives acceleration of the body.
Reason: Greater the slope of distance time graph, more is the speed of the body.
→
A statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as:
Assertion: Sound wave is an electromagnetic wave.
Reason: Speed of sound in solid is less than air.
→
In the following questions, a statement of Assertion $(A)$ is followed by a statement of Reason $(R)$. Mark the correct choice as:
Assertion: According to Bohr's model, the orbits of an atom are also called energy levels.
Reason: Orbits are the spheres containing definite value of energy.
→
In the following questions, a statement of Assertion $(A)$ is followed by a statement of Reason $(R)$. Mark the correct choice as:
Assertion: Camphor disappears without leaving any residue.
Reason: Camphor undergoes sublimation.
→
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: Infectious diseases can be treated by two ways, one by reducing the effect of the disease and the other by killing the cause of the disease.
Reason: Fever, pain, loose motion are symptoms.
→
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: The formula of aluminium sulphate is $Al_2(SO_4)_3$.
Reason: The valency of $Al$ is $3$ and charge on $SO_4{}^{2-}$.
→
Assertion $(A):$ A tiger can accelerate from rest at the rate of $4\ m/s^2$
Reason $(R):$ The velocity attained by it in $10s$ is $40\ m/s.$
→
In the following Questions, the Assertion and Reason have been put forward. Read the statements carefully and choose the correct alternative from the following:
Assertion: Work done by the force of friction is always negative.
Reason: Friction force always acts in opposite direction to that of motion of the body.
→