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According to Newton second law of motion...

According to Newton second law of motion

A

`F=m times v`

B

`f= m times a`

C

`f=m/a`

D

`f=m/v`

Text Solution

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The correct Answer is:
**Step-by-Step Solution:** 1. **Understanding Newton's Second Law of Motion**: Newton's second law states that the force acting on an object is equal to the rate of change of its momentum. Mathematically, this can be expressed as: \[ F \propto \frac{dP}{dt} \] where \( F \) is the force, \( P \) is the momentum, and \( t \) is time. 2. **Converting Proportionality to Equality**: To convert the proportionality into an equality, we introduce a constant of proportionality. In this case, we can express it as: \[ F = k \cdot \frac{dP}{dt} \] By convention, we take \( k = 1 \), leading to: \[ F = \frac{dP}{dt} \] 3. **Expressing Momentum**: The momentum \( P \) of an object is defined as the product of its mass \( m \) and its velocity \( v \): \[ P = mv \] Therefore, the change in momentum can be expressed as: \[ \Delta P = P_2 - P_1 = mv_2 - mv_1 \] 4. **Calculating Rate of Change of Momentum**: The rate of change of momentum with respect to time is given by: \[ \frac{dP}{dt} = \frac{P_2 - P_1}{t} = \frac{mv_2 - mv_1}{t} \] 5. **Substituting into the Force Equation**: Substituting the expression for the rate of change of momentum into the force equation gives: \[ F = \frac{mv_2 - mv_1}{t} \] 6. **Simplifying the Expression**: Factoring out the mass \( m \) from the equation: \[ F = m \cdot \frac{(v_2 - v_1)}{t} \] The term \( \frac{(v_2 - v_1)}{t} \) represents acceleration \( a \): \[ F = ma \] 7. **Conclusion**: Thus, the mathematical statement of Newton's second law of motion is: \[ F = ma \] This indicates that the force acting on an object is equal to the mass of the object multiplied by its acceleration. 8. **Choosing the Correct Option**: Based on the derived equation \( F = ma \), we can conclude that the correct option is the one that states \( F = ma \). ---

**Step-by-Step Solution:** 1. **Understanding Newton's Second Law of Motion**: Newton's second law states that the force acting on an object is equal to the rate of change of its momentum. Mathematically, this can be expressed as: \[ F \propto \frac{dP}{dt} \] where \( F \) is the force, \( P \) is the momentum, and \( t \) is time. ...
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Knowledge Check

  • Assertion: Newton's second law of motion gives the measurement of force. Reason: According to Newton's second law of motion, force is directly proportional to the rate of change of momentum.

    A
    If both assertion `&` Reason are True `&` the Reason is a corrrect explanation of the Asserion.
    B
    If both Assertion `&` Reason are True but Reason is not correct explanation of the Assertion.
    C
    If Assertion is Trie but the Reason is False.
    D
    If both Assertion `&` Reason are false
  • Assertion: Newton's second law of motion given the measurement of force. Reason: According to Newton's second law of motion, force is directly proportional to the rate of change of momentum.

    A
    If both assertion and reason are ture and reason is the correct explanation of assertion.
    B
    If both assertion and reason are ture but reason is not the correct explanation of assertion.
    C
    If assertion is ture but reason is false.
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  • When a body is moving uniformly along a straight line and there is no force of friction, acceleration/retardation of the body. According to Newton's second law of motion, the magnitude of force acting on a body is the product of mass and acceleration of the body The distance - time table of an object in motion is given below The force acting on the object

    A
    increases
    B
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