# Finding Force with T and V given

• mom2maxncoop
In summary: They do it because they enjoy helping people out. So don't feel bad about asking questions, that's what this forum is all about! :)In summary, a child pushes a block of wood across a smooth table with a mass of 0.72kg and a coefficient of kinetic friction of 0.64. After 2.0 seconds, the block has a velocity of 1.6m/s [forward]. The net force on the block is 7.06N and the force of friction is 4.52N. To find the force with which the child pushes on the block, the formulas v = v0 + at and Fresultant = ma can be used. The resultant force on the block is
mom2maxncoop

## Homework Statement

A child pushes a block of wood with a mass of 0.72kg across a smooth table. The block starts from a position of rest and after 2.0s it has a velocity of 1.6m/s [forward]. The coefficient of kinetic friction is 0.64.

I have already determined that
F$_{net}$= 7.06N
F$_{f}$= 4.52 N

Find the force with which the child actually pushes on the block of wood

## Homework Equations

I have no clue what formula to use here in order to calculate this. Any sort of guidance be great! -Thanks

## The Attempt at a Solution

I know that this has something to do with the velocity and it being 1.6m/s after 2.0 but I don't know even know where to being to find which formula to use!

Hi mom2maxncoop! Welcome to PF!

You have the force of friction right!

Do you know the following formulas?
v = v0 + a t
Fresultant = m a

Btw, what you have named Fnet is not the net force, but the force of gravity on the block, also called weight.

From the first formula you can calculate the acceleration a.
From the second formula you can calculate the resultant force on the block.
And finally you can calculate the force that the child exerts.

Hi, I'm new here. I just thought I'd hijack mom2maxncoop's thread and revive it because I'm having a little difficulty with the same question.

Using the formula:

F resultant = m a
F resultant = (0.72kg) (0.8m/s^2)
F resultant = 0.576N

So, is this the net horizontal force exerted on the block of wood? If so, then I figured that the frictional force is:

F friction = u Fn
F friction = (0.64) (7.06N)
F friction = 4.52N

And so the applied force must be 4.52N + 0.58N = 5.1N

Correct? Thanks in advance!

Welcome to PF too, Seinfeld4!

Yes, you have it entirely correct.
Nice to see this thread had some use after all, since the OP never came back.

Thanks for the quick reply, and thanks for the welcome!

I have a feeling I'm going to be asking a lot more questions around here in the future. I feel a little bad though, because I'm just starting to learn about physics, so I'll be asking for help WAY more than I'll be dishing it out. Oh well, thanks again!

Don't worry about it. :)
The homework helpers don't help because of any expected return favor.

Last edited:

## What is the formula for finding force with T and V given?

The formula for finding force with T and V given is F = m x a, where F is force, m is mass, and a is acceleration.

## How do I find the mass using the given force and acceleration?

To find the mass, divide the force by the acceleration. This can be written as m = F/a.

## What units are used for force, mass, and acceleration?

Force is typically measured in Newtons (N), mass in kilograms (kg), and acceleration in meters per second squared (m/s^2).

## Can I use this formula for any type of force?

This formula can be used for calculating any type of force, as long as the mass and acceleration are known.

## What is the relationship between force, mass, and acceleration?

The relationship between force, mass, and acceleration is described by Newton's Second Law of Motion, which states that the force applied to an object is directly proportional to its mass and acceleration.

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