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Select the correct statement(s). I. A ...

Select the correct statement(s).
I. A person receives more injury when he fall on hard rock as compared with that when he falls on a cushion.
II. In the first case, time of reaction is more.
III. In the first case, time of reaction is less.
IV. It is a case involving impulse.

A

I and II are correct

B

I and II are correct

C

I, III and IV are correct

D

I, II and IV are correct

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, let's analyze each statement one by one: ### Step 1: Analyze Statement I **Statement I:** A person receives more injury when he falls on hard rock as compared with that when he falls on a cushion. - **Explanation:** When a person falls on a hard surface like rock, the deceleration is very rapid, leading to a high force exerted on the body in a short time. This results in more severe injuries. On the other hand, a cushion absorbs some of the impact and allows the person to decelerate more gradually, resulting in less injury. - **Conclusion:** This statement is **correct**. ### Step 2: Analyze Statement II **Statement II:** In the first case, time of reaction is more. - **Explanation:** The time of reaction refers to the time taken for the body to come to rest after hitting the surface. In the case of a hard surface, the time taken to stop is very short because the deceleration is abrupt. Therefore, the time of reaction is **not more**. - **Conclusion:** This statement is **incorrect**. ### Step 3: Analyze Statement III **Statement III:** In the first case, time of reaction is less. - **Explanation:** As explained in the previous step, when falling on a hard surface, the time taken to come to rest is indeed less due to the abrupt stop. Therefore, this statement is true. - **Conclusion:** This statement is **correct**. ### Step 4: Analyze Statement IV **Statement IV:** It is a case involving impulse. - **Explanation:** Impulse is defined as the change in momentum, which occurs over a short time when a force is applied. In the case of falling on a hard surface, the change in momentum happens quickly, and thus impulse is involved. - **Conclusion:** This statement is **correct**. ### Final Conclusion After analyzing all the statements: - Statement I: Correct - Statement II: Incorrect - Statement III: Correct - Statement IV: Correct Thus, the correct statements are I, III, and IV. ### Summary of Correct Statements: The correct statements are: - I. A person receives more injury when he falls on hard rock as compared with that when he falls on a cushion. - III. In the first case, time of reaction is less. - IV. It is a case involving impulse.
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