Newton’s Second Law of Motion:
Newton’s second law of motion states that the rate of change of momentum of an object is directly proportional to the net external force acting on it and occurs in the direction of the force. Mathematically, it can be expressed as:
F = ma
Where F is the net external force acting on the object, m is the mass of the object, and a is the acceleration produced.

Impulse:
Impulse is defined as the product of the force acting on an object and the time interval during which the force acts. It is given by the equation:
Impulse = F Δt
Where F is the force applied and Δt is the time interval for which the force acts.

Momentum:
Momentum is defined as the product of an object’s mass and its velocity. It is given by the equation:
Momentum = mass × velocity
Or
P = mv
Where P is the momentum of the object, m is its mass, and v is its velocity.

Impulse-Momentum Theorem:
The impulse-momentum theorem states that the change in momentum of an object is equal to the impulse applied to it. Mathematically, it can be expressed as:
ΔP = Impulse
Or
ΔP = F Δt
Where ΔP is the change in momentum and F Δt is the impulse.

Assertion and Reason:
The assertion that impulse is equal to the change in momentum is correct. However, the reason that impulse and momentum have different SI units is not a valid explanation for this assertion.

Explanation:
- Impulse is defined as the product of force and time, while momentum is defined as the product of mass and velocity.
- The SI unit of force is Newton (N), and the SI unit of time is seconds (s). Therefore, the SI unit of impulse is Ns.
- The SI unit of mass is kilogram (kg), and the SI unit of velocity is meters per second (m/s). Therefore, the SI unit of momentum is kg m/s.
- Although impulse and momentum have different SI units, they are still related to each other through the impulse-momentum theorem.
- According to the impulse-momentum theorem, the change in momentum of an object is equal to the impulse applied to it.
- This means that the product of force and time (impulse) is equal to the change in momentum.
- Therefore, the assertion that impulse is equal to the change in momentum is correct, regardless of the fact that they have different SI units.
- The reason given in the assertion is incorrect because the fact that impulse and momentum have different SI units does not affect their relationship or the validity of the impulse-momentum theorem.
- The impulse-momentum theorem is derived from Newton’s second law of motion, which relates force, mass, acceleration, and time. The units of force, mass, and time determine the units of impulse and momentum, but they do not affect their relationship.

A is wrong and r is correct