An 800-N passenger in a car presses against the car door with a 200 N force when the car makes a left turn at 13 m/s.The (faulty)door will pop open under a force of 800 N.Of the following, the least speed for which the man is thrown out of the car is:
A)14 m/s
B)19 m/s
C)20 m/s
D)26 m/s
E)52 m/s

Question

Quizplus · Accepted Answer

The force of the man on the door is 200 N. The force of the car on the man is 800 N. The net force on the man is 600 N. The acceleration of the man is 600 N / 800 kg = 0.75 m/s^2. The speed of the man when he is thrown out of the car is 13 m/s + 0.75 m/s^2 * t, where t is the time it takes for the man to be thrown out of the car. The time it takes for the man to be thrown out of the car is 800 N / 600 N/s = 1.33 s. The speed of the man when he is thrown out of the car is 13 m/s + 0.75 m/s^2 * 1.33 s = 20 m/s.

An 800-N Passenger in a Car Presses Against the Car