With reference to 'Muscular Force', consider the following statements: 1. It is the force resulting due to the action of muscles. 2. It can be applied to an object without being in contact with it. 3. It is responsible for the expansion and contraction of lungs during breathing. Which of the statements given above are correct?

The correct option is (c). Explanation Force is an external agency that changes or tends to change the state of rest or motion of a body. Forces are broadly classified into contact forces (requiring physical interaction) and non-contact forces (acting from a distance). Muscular force is a primary example of a contact force generated by biological organisms. Statement-wise Analysis - Statement 1 is Correct: Muscular force is the force exerted by the muscles of the body. It is generated through the contraction and relaxation of muscle fibers, allowing animals and humans to perform various activities like lifting, walking, or running. - Statement 2 is Incorrect: Muscular force is strictly a contact force. It cannot be applied to an object from a distance; physical contact between the body (or an extension of the body, like a stick or rope) and the object is mandatory for this force to act. This distinguishes it from non-contact forces like gravitational, magnetic, or electrostatic forces. - Statement 3 is Correct: The process of breathing involves the expansion and contraction of the lungs, which is driven by the movement of the diaphragm and the intercostal muscles between the ribs. These movements are the result of muscular force exerted by the respiratory muscles. Key Takeaway Muscular force is a contact force produced by the action of muscles and requires physical interaction with an object to be effective.

With reference to 'Muscular Force',… - NCERT Class 8 Science MCQ

NCERT Class 8 Science — Chapter 1: Force and pressure

mcqmedium

With reference to 'Muscular Force', consider the following statements:

It is the force resulting due to the action of muscles.
It can be applied to an object without being in contact with it.
It is responsible for the expansion and contraction of lungs during breathing.

Which of the statements given above are correct?

NCERT textbook question

From NCERT Science - class 8 · Page 101

Options

A1 and 2 only
B2 only
C1 and 3 only
D1, 2 and 3

Did you get this right?

Solution

The correct option is (c).

Explanation

Force is an external agency that changes or tends to change the state of rest or motion of a body. Forces are broadly classified into contact forces (requiring physical interaction) and non-contact forces (acting from a distance). Muscular force is a primary example of a contact force generated by biological organisms.

Statement-wise Analysis

Statement 1 is Correct: Muscular force is the force exerted by the muscles of the body. It is generated through the contraction and relaxation of muscle fibers, allowing animals and humans to perform various activities like lifting, walking, or running.
Statement 2 is Incorrect: Muscular force is strictly a contact force. It cannot be applied to an object from a distance; physical contact between the body (or an extension of the body, like a stick or rope) and the object is mandatory for this force to act. This distinguishes it from non-contact forces like gravitational, magnetic, or electrostatic forces.
Statement 3 is Correct: The process of breathing involves the expansion and contraction of the lungs, which is driven by the movement of the diaphragm and the intercostal muscles between the ribs. These movements are the result of muscular force exerted by the respiratory muscles.

Key Takeaway

Muscular force is a contact force produced by the action of muscles and requires physical interaction with an object to be effective.

Your note

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