Question

A 2,000-kg car traveling at 40 m/s hits a wall with a force of 40,000 N and comes to a stop. What was the impact time?

Answer 1

Answer:

The impact time is equal to $2$ seconds

Explanation:

Given -

Force (F) $= 40,000$ N or $\frac{Kg-m}{s^2}$

Mass(M) $= 2,000$ Kg

Initial Velocity (u) $= 40\frac{m}{s}$

Final Velocity (v) $= 0\frac{m}{s}$

Force exerted by any body is equal to the product of its mass and acceleration

Hence, mathematically it can be represented as

$F = M * a$

Substituting the given values, we get -

$40,000 = 2,000 * a\\a = 20 \frac{m}{s^2}$

As per Newton's first law of motion,

$v = u - at$ in case of deceleration

Substituting the available values in above equation, we get -

$0 = 40 - 20 * t\\40 = 20*t\\t = \frac{40}{20} \\t = 2$ seconds

The impact time is equal to $2$ seconds

Answer 2

If I did my math correct, the answer would be 2 seconds.