Question

A 50-kg block of cement is pulled upward (not sideways!) with a force of 600 N. What is its acceleration?

Answer 1

`2.2m"/"s^2`

Explanation:

First, we need to use Newton's second law of motion, which states that

`F=ma`

`F` is the force in newtons `(N)`

`m` is the mass of the object in kilograms

`a` is the acceleration of the object in `m"/"s^2`

So, plugging in,

`600=50a`, `a=600/50=12`

So, the acceleration is right now `12m"/"s^2`. But, it is being pulled up, so gravity, which has an acceleration of `~~9.8m"/"s^2`, pulls it in the opposite direction, which is down.

That means, that we need to subtract.

`12m"/"s^2-9.8m"/"s^2=2.2m"/"s^2`