Question

**

What happens when a person pulls upward on the box as shown with a force
equal to, or greater than the box's weight?
Let Fp = 100.0 N rather than 40.0 N as shown.​

Answer 1

The object will have an upward acceleration

Step-by-step explanation:

Let's consider the forces applied on the box. We have only two forces:

- The applied force of push,
`F_p`, downward

- The force of gravity,
`W`, (also known as weight of the object), downward

Therefore, the net force on the box is:

`F_(net)=F_p -W`

Here, we know that force applied is equal or greater than the weight, so

`F_p \geq W`

And therefore the net force is greater than zero:

`F_(net)\geq 0` (1)

According to Newton's second law of motion, the net force on the box is equal to the product between its mass and its acceleration:

`F_(net)=ma`

where

m is the mass of the box

a is its acceleration

Given (1), this means that

`a\geq 0`

Therefore, the box will have an upward acceleration.

In this case force example we have:

`F_p = 100 N\\W = 40 N`

So the mass of the box is

`m=(W)/(g)=(40)/(10)=4 kg`

So the net force is

`F_(net)=F_p-W=100-40=60 N`

And the acceleration is

`a=(F_(net))/(m)=(60)/(4)=15 m/s^2`