It is defined as the integral of force with respect to time.

It is defined as the integral of force with respect to time.

• A. impulse
• B. velocity
• C. momentum
• D. acceleration

Answer: (A)

Impulse is the quantity defined as the integral of force with respect to time. This comes from F = dp/dt: force is the rate of change of momentum. If you integrate both sides over a time interval, you get the change in momentum, Δp = ∫ F dt. So the area under the force–time curve—the impulse—tells you how much the body's momentum changes during that interval. In practical terms, a force acting longer or with greater magnitude yields a larger impulse, and thus a bigger change in velocity for a given mass. Other quantities differ in what they describe: velocity is how fast and in what direction you’re moving; momentum is mass times velocity; acceleration is how quickly velocity changes. They’re related concepts, but the integral of force over time specifically measures the impulse that changes momentum. Units work out as N·s, which is equivalent to kg·m/s.

Impulse is the quantity defined as the integral of force with respect to time. This comes from F = dp/dt: force is the rate of change of momentum. If you integrate both sides over a time interval, you get the change in momentum, Δp = ∫ F dt. So the area under the force–time curve—the impulse—tells you how much the body's momentum changes during that interval. In practical terms, a force acting longer or with greater magnitude yields a larger impulse, and thus a bigger change in velocity for a given mass.

Other quantities differ in what they describe: velocity is how fast and in what direction you’re moving; momentum is mass times velocity; acceleration is how quickly velocity changes. They’re related concepts, but the integral of force over time specifically measures the impulse that changes momentum. Units work out as N·s, which is equivalent to kg·m/s.