The answer would be B the method of rock formation
A rolling friction jdisns
Answer:
F= 5195.625 N
Explanation:
To obtain the force needed to hold the child, we need to know the aceleration in which the car is breaking.
Aceleration is equal to velocity divided by the time of breaking
In international system, velocity [m/s] is
v= (62 mi/h)*(1609 m/mi)*(1 h/3600 s)
v= 27.71 m/s
Now, we part the velocity by the time that is 0.08 seconds
a= v/t= (27.71 m/s)/(0.08 s)
a= 346.375 m/
The force in agreement with the Newton's second law is
F=m*a = 15 Kg*346.375 m/
F= 5195.625 N
(Note: 1 N = 1 Kg*m/
)
D.gravity is your answer hope this helps