Answer:
It takes approximately 0.625 seconds for the person to be stopped by the airbag.
Step-by-step explanation:
We can use the formula for average acceleration to solve this problem:
a = (v_f - v_i) / t
where:
a = average acceleration
v_f = final velocity (0 m/s)
v_i = initial velocity (15 m/s)
t = time
We know that the airbag provides a stopping force of 1200 N, which is equal to the net force on the person-car system. We can use Newton's second law of motion to find the acceleration of the person:
F_net = ma
where:
F_net = net force (1200 N)
m = mass of person (50 kg)
a = acceleration
Solving for a, we get:
a = F_net / m
a = 1200 N / 50 kg
a = 24 m/s^2
Now we can substitute the values of a, v_f, and v_i into the formula for average acceleration and solve for t:
a = (v_f - v_i) / t
24 m/s^2 = (0 m/s - 15 m/s) / t
t = -15 m/s / 24 m/s^2
t = 0.625 s
Therefore, it takes approximately 0.625 seconds for the person to be stopped by the airbag.