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Physics Section 6.1 Solve momentum and impulse problems. Momentum is the product of the mass and the velocity of an object. p = mv p =momentum ( kg·m /s) m = mass (kg) v = velocity (m/s).
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Physics Section 6.1Solve momentum and impulse problems Momentum is the product of the mass and the velocity of an object. p = mvp =momentum (kg·m/s) m = mass (kg) v = velocity (m/s) Momentum is a vector quantity. It has the same direction as the velocity.
Problem A 1200 kg car has a velocity of 85 km/h to the north. Find its momentum.
Impulseis the product of the force and time interval over which the force acts on an object. Impulse – Momentum Theorem F(Δt) = ΔpF = force (N) t = time (s) p = momentum (kg·m/s) F(Δt) = mvf - mvi Force x time = change in momentum. An impulse causes a change in momentum.
problem A force of 280 N is applied to a stationary baseball with a mass of .32 kg. The duration of the force is .12 s. Find the change in the ball’s velocity.
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problem A .50 kg football is thrown with a velocity of 15 m/s to the right. A stationary receiver catches the ball and brings it to rest in .020 s. What is the force exerted on the ball by the receiver?
problem Two trucks are traveling at 50 km/h. The first truck has a mass of 2500 kg and the second truck has a mass of 5000 kg. How do the stopping times for the truck compare?
problem A 2240 kg car traveling west slows down from 20.0 m/s to 5.00 m/s. How long does it take to decelerate if the brakes apply a force of 8410 N east. How far does the car travel during this period?
problem A 3250 kg car is traveling 20.0 m/s and brakes to a stop in 5.33 s. What force was applied?
assignment Page 204 problems 1 - 5