Assertion (A) & Reason (B) MCQ

MCQ 11 Mark

Assertion (A): Isotopes are electrically neutral.
Reason (R): Isotopes are species with same mass number but different atomic numbers.

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: Isotopes are species with same atomic number but different mass numbers.

View full question & answer→

MCQ 21 Mark

Assertion (A): A nail is inserted in the trunk of a tree at a height of 1 metre from the ground level. After 3 years, the nail is still present there.
Reason (R): The girth of the stem or root increases due to apical meristem (cambium).

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: The nail will remain at the same position even after 3 years. This is because a plant or tree grows from its tip (stem or root) not from the point at which it joins the ground. So, the tree will grow but the nail will remain at the same place on the tree trunk.

View full question & answer→

MCQ 31 Mark

Assertion (A): It is easier to cook food at high altitudes.
Reason (R): The boiling point of water decreases at high altitudes.

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
C
A is true but R is false.
✓
A is false but R is true.

Answer

Correct option: D.

A is false but R is true.

(d) A is false but R is true.
Explanation: It is difficult to cook food at high altitudes since the boiling point of water decreases at high altitudes and it does

not provide sufficiently high temperature to the food to get cooked.

View full question & answer→

MCQ 41 Mark

Assertion (A): The speedometer of an automobile measure the average speed of the automobile.
Reason (R): Average velocity is equal to total displacement per total time-taken.

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
C
A is true but R is false.
✓
A is false but R is true.

Answer

Correct option: D.

A is false but R is true.

(d) A is false but R is true.
Explanation: Speedometer measures instantaneous speed of automobile.

View full question & answer→

Science Assertion (A) & Reason (B) MCQ

Take a timed test