Force and Pressure 8 Assignment 06

Answers are at the end.

Assertion and Reasoning Questions

For each question, evaluate the Assertion (A) and Reasoning (R), then choose the correct option:

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.
D) A is false, but R is true.

1.

Assertion (A): A force can start an object moving from rest.
Reasoning (R): Pushing a ball on a table causes it to move.

2.

Assertion (A): Gases exert pressure on the walls of their containers.
Reasoning (R): Inflating a balloon requires closing its mouth to trap the air pressure inside.

3.

Assertion (A): A force always changes the state of motion of an object.
Reasoning (R): Pushing a heavy box may not move it if the force is too weak.

4.

Assertion (A): The gravitational force is a contact force.
Reasoning (R): Objects fall to the ground because Earth pulls them without touching them directly.

5.

Assertion (A): The pressure exerted by a liquid increases with the height of the liquid column.
Reasoning (R): In Activity 8.8, the rubber sheet bulges more as more water is added to the pipe.

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Answers:

1. A) Both A and R are true, and R is the correct explanation of A.
   • Explanation: Pushing starts motion
2. A) Both A and R are true, and R is the correct explanation of A.
   • Explanation: Trapped air exerts pressure
3. D) A is false, but R is true.
   • Explanation: Force may not change motion if insufficient
4. D) A is false, but R is true.
   • Explanation: Gravity is non-contact
5. A) Both A and R are true, and R is the correct explanation of A.
   • Explanation: Bulge increases with height = pressure increase