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Assertion : A bullet is fired from a r...

Assertion : A bullet is fired from a rifle. If the rifle recoils freely, the kinetic energy of rifle is more than that of the bullet.
Reason : In the case of rifle bullet system the law of conservation of momentum violates.

A

Assertion is correct, reason is correct, reason is a correct explanation for assertion.

B

Assertion is correct, reason is correct, reason is not a correct explanation for assertion

C

Assertion is incorrect, reason is incorrect

D

Assertion is incorrect, reason is correct

Text Solution

AI Generated Solution

The correct Answer is:
To solve the given question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that when a bullet is fired from a rifle, if the rifle recoils freely, the kinetic energy of the rifle is more than that of the bullet. - **Analysis**: The kinetic energy (KE) of an object is given by the formula: \[ KE = \frac{1}{2} mv^2 \] where \( m \) is the mass and \( v \) is the velocity of the object. 2. **Momentum Conservation**: When the bullet is fired, the system (bullet + rifle) is isolated, and thus, the law of conservation of momentum applies. The total momentum before firing (which is zero) must equal the total momentum after firing. - **Mathematical Representation**: \[ 0 = m_b v_b + m_r v_r \] where \( m_b \) is the mass of the bullet, \( v_b \) is the velocity of the bullet, \( m_r \) is the mass of the rifle, and \( v_r \) is the recoil velocity of the rifle. 3. **Comparison of Mass and Velocity**: - The mass of the bullet (\( m_b \)) is much less than the mass of the rifle (\( m_r \)). - To conserve momentum, if the bullet has a high velocity \( v_b \), the rifle must have a much lower velocity \( v_r \) in the opposite direction. 4. **Kinetic Energy Calculation**: - The kinetic energy of the bullet: \[ KE_b = \frac{1}{2} m_b v_b^2 \] - The kinetic energy of the rifle: \[ KE_r = \frac{1}{2} m_r v_r^2 \] - Since \( m_b \) is much smaller than \( m_r \) and \( v_b \) is much larger than \( v_r \), it can be shown that: \[ KE_b > KE_r \] - Therefore, the assertion that the kinetic energy of the rifle is more than that of the bullet is **incorrect**. 5. **Understanding the Reason**: The reason states that in the case of the rifle-bullet system, the law of conservation of momentum violates. - **Analysis**: This statement is also incorrect. The law of conservation of momentum holds true in this scenario as there are no external forces acting on the system. The momentum before and after firing remains conserved. ### Conclusion: Both the assertion and the reason are incorrect. Therefore, the correct answer to the question is that both statements are false.

To solve the given question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that when a bullet is fired from a rifle, if the rifle recoils freely, the kinetic energy of the rifle is more than that of the bullet. - **Analysis**: ...
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