The rate of change of linear momentum is __________.

CONCEPT:

• Momentum: A property of a body in motion that is equal to the product of the body's mass and velocity is called momentum.

P = mv

where P is the momentum of the body, m is the mass of the body, and v is the velocity of the body.

• Newton's Second Law of Motion: It says that the net external force on a system or body is equal to the change in momentum of the system or body divided by the time over which it changes. 

Mathematically:

\(F_{ext} = {Δ p \over Δ t}\)

where Fext is the external force on the system, Δp is the change in momentum, and Δt is the change in time.

EXPLANATION:

Newton's second law of motion in momentum form can be written as:

\(F_{ext} = {Δ p \over Δ t}\)

which says the rate of change of momentum \( {Δ p \over Δ t}\) is equal to the external force on a system.

So the correct answer is option 1.