Force and Pressure 8 Assignment 02

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 change the shape of an object.
Reasoning (R): Pressing a lump of dough with hands demonstrates that force alters its state of motion.

2.

Assertion (A): Liquids exert pressure on the walls of their container.
Reasoning (R): Water streams from holes at the same depth in a bottle fall at equal distances, showing equal pressure.

3.

Assertion (A): Friction is a non-contact force.
Reasoning (R): It slows down a moving object like a ball rolling on the ground.

4.

Assertion (A): The net force on an object is zero if two equal forces act in opposite directions.
Reasoning (R): Forces in the same direction add up, while opposing forces subtract.

5.

Assertion (A): Atmospheric pressure is very weak and barely affects us.
Reasoning (R): The force on a 15 cm × 15 cm area is equivalent to 225 kg, but our internal pressure balances it.

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Answers :

1. C) A is true, but R is false.
   • Explanation: Force changes dough’s shape, not motion
2. A) Both A and R are true, and R is the correct explanation of A.
   • Explanation: Equal streams prove equal pressure at same depth.
3. D) A is false, but R is true.
   • Explanation: Friction is a contact force; it slows objects .
4. A) Both A and R are true, and R is the correct explanation of A.
   • Explanation: Equal opposing forces cancel out
5. D) A is false, but R is true.
   • Explanation: Atmospheric pressure is strong (2250 N), balanced by internal pressure