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A 2000 Kg car is driving 15 m/s. It drives head-on into a giant spring attached

to a brick wall. The spring compresses 8 meters after the impact. What is the
spring coefficient of the giant spring? *

User Marcelo MD
by
6.7k points

1 Answer

13 votes

Answer:

The spring constant is k=7031.25

Step-by-step explanation:

We start by using the conservation of mechanical energy:

Ui + Ki = Uf + Kf

the Ui (initial potential energy) is zero since the spring is relaxed.

In the final situation, the Kf (final kinetic energy is zero since the car and spring are NOT in motion)

Then we have:


K_i=U_f\\(1)/(2) m*v^2=(1)/(2) k*(\Delta x)^2\\(1)/(2) 2000*15^2=(1)/(2) k*(8)^2\\k=7031.25

User Mre
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