Consider the following everyday experiences: 1. Dust coming out of a carpet when beaten with a stick. 2. Leaves getting detached from a tree when shaken vigorously is unrelated to the property of inertia. 3. A coin falling into a tumbler when the card below it is flicked. Which of the above can be explained by the Law of Inertia?

The correct option is (c). Explanation The application of Newton’s First Law of Motion, also known as the Law of Inertia. According to this law, an object at rest tends to remain at rest, and an object in motion tends to remain in motion, unless acted upon by an external unbalanced force. The specific type of inertia involved here is the Inertia of Rest. Statement-wise Analysis: - Statement 1 is Correct: When a carpet is beaten with a stick, the carpet is set into sudden motion. However, the dust particles trapped in it tend to remain at rest due to the inertia of rest. As a result, the dust separates from the moving carpet. - Statement 2 is Incorrect: The statement claims that leaves detaching from a tree is unrelated to inertia. This is factually wrong. When a tree is shaken vigorously, the branches come into motion, but the leaves tend to remain at rest due to the inertia of rest. This resistance to motion causes the stem to break and the leaves to detach. Since the statement explicitly denies the role of inertia, it is an incorrect proposition and cannot be categorized as an experience explained by the law in this context. - Statement 3 is Correct: When the card is flicked, the force acts only on the card, setting it into motion. The coin placed on top tends to maintain its state of rest due to the inertia of rest. Consequently, the card moves away, and the coin falls vertically into the tumbler due to gravity. Key Takeaway: Inertia of Rest is the inherent property of a body to resist any change in its state of rest. Common examples include dust flying off a beaten carpet, passengers falling backward when a bus starts suddenly, and fruits or leaves falling when a tree is shaken.

Consider the following everyday… - NCERT Class 9 Science MCQ

NCERT Class 9 Science — Chapter 2: Force and laws of motion

mcqmedium

Consider the following everyday experiences:

Dust coming out of a carpet when beaten with a stick.
Leaves getting detached from a tree when shaken vigorously is unrelated to the property of inertia.
A coin falling into a tumbler when the card below it is flicked.

Which of the above can be explained by the Law of Inertia?

NCERT textbook question

From NCERT Science - class 9 · Page 5

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

The application of Newton’s First Law of Motion, also known as the Law of Inertia. According to this law, an object at rest tends to remain at rest, and an object in motion tends to remain in motion, unless acted upon by an external unbalanced force. The specific type of inertia involved here is the Inertia of Rest.

Statement-wise Analysis:

Statement 1 is Correct: When a carpet is beaten with a stick, the carpet is set into sudden motion. However, the dust particles trapped in it tend to remain at rest due to the inertia of rest. As a result, the dust separates from the moving carpet.
Statement 2 is Incorrect: The statement claims that leaves detaching from a tree is unrelated to inertia. This is factually wrong. When a tree is shaken vigorously, the branches come into motion, but the leaves tend to remain at rest due to the inertia of rest. This resistance to motion causes the stem to break and the leaves to detach. Since the statement explicitly denies the role of inertia, it is an incorrect proposition and cannot be categorized as an experience explained by the law in this context.
Statement 3 is Correct: When the card is flicked, the force acts only on the card, setting it into motion. The coin placed on top tends to maintain its state of rest due to the inertia of rest. Consequently, the card moves away, and the coin falls vertically into the tumbler due to gravity.

Key Takeaway:
Inertia of Rest is the inherent property of a body to resist any change in its state of rest. Common examples include dust flying off a beaten carpet, passengers falling backward when a bus starts suddenly, and fruits or leaves falling when a tree is shaken.

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