Question

A 2000-kg car traveling at 40m/s hits a wall with a force of 40,000N and comes to a stop what was the impact time?

A-0.5s
B-2s
C-400s
D-800s

Answer 1

D- 800 s I think I did (40,000)(40)/2000 idk if this is the right answer

Answer 2

Option (B)

Step-by-step explanation:

mass of car, m = 2000 kg, initial velocity of car, u = 40 m/s,

Force, F = 40,000 N, Final velocity, v = 0 m/s

Let the impact time be t.

By use of Newton's second law

F = m a

where, a be the acceleration and m be the mass.

40000 = 2000 x a

a = 20 m/s^2

Acceleration is negative because the car is stopped.

Use first equation of motion,

v = u + a x t

0 = 40 - 20 x t

t = 2 second