A car is traveling due east at when the driver applies the brakes while a strong…
PHYSICS · Multi-part · AP · Physics 1: Algebra-based · Linear Momentum · Linear Momentum
Problem
A 1200kg car is traveling due east at 18ms−1 when the driver applies the brakes while a strong cross-wind blows toward the south. During a 0.80s interval of simultaneous braking and wind, two nearly constant forces act on the car:
• a braking force of magnitude 5.0×103N directed due west, and
• a wind force of unknown magnitude Fw directed due north.
At the end of the interval the car’s velocity is 12ms−1 directed 25∘ north of east. Ignore any other horizontal forces and treat the car as a particle of constant mass.
(a) Determine the car’s change in momentum during the 0.80s interval, expressing your answer in component form relative to the east and north directions.
(b) Calculate the impulse delivered by the braking force during the interval, stating its components.
(c) Using your results from parts (a) and (b), determine the magnitude of the impulse delivered by the wind.
(d) Hence compute the magnitude of the wind force Fw acting on the car.