Answer:
F = 7.143 kN
Explanation:
given,
time taken to apply break = 1.05 s
car slows down from 15 m/s to 9 m/s
mass of the car = 1250 Kg
force is equal to the change in momentum with respect to time.
F = -7142.85 N
F = - 7.143 kN
Force is acting opposite direction of velocity of car i.e. the sign is negative.
im probably wrong but probably increase because if they get closer the static/sparks to cause a reaction
Answer:
Explanation:
Given
Force=18lb
extension=8in
Using Hooke's law to get the spring constant(k)
F=ke
Then,
K=f/e
K=18/8
K=2.25lb/in
Work done by spring is given by
W=1/2Fe
Or W=1/2ke²
Then,
Work done in stretching the spring to 14in
W=1/2ke²
W=0.5×2.25×14²
W=220.5lbin
1 Inch-pounds Force to Joules = 0.113J
Then, to joules
W=0.133×220.5
W=29.33J
B. should be your answer!