Question

A 70 kg meteor smashes into the earth, hitting with 100,000 N of force. If the object was originally traveling at 20,000 m/s, how long will it take it to come to a rest?

Answer 1

t = 14 s

Step-by-step explanation:

First, we need to find the acceleration of the meteor by using Newton's s Second Law, as follows:

`F = ma`

where,

F = Unbalanced Force = 100000 N

m = mass of meteor = 70 kg

a = acceleration of meteor = ?

Therefore,

`100000\ N = (70\ kg)(a)\\a = ((100000\ N))/(70\ kg)\\\\a = 1428.57\ m/s^2`

a = -1428.57 m/s² (negative sign de to deceleration)

Now, we use general formula of acceleration to find time:

`a = (\Delta v)/(t)\\\\t = (\Delta v)/(a)`

where,

t = time taken = ?

Δv = change in speed = 0m/s - 20000 m/s = - 20000 m/s

Therefore,

`t = (- 20000\ m/s)/(-1428.57\ m/s^2)\\\\`

t = 14 s