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**
1. Homework Statement **

A 60 kg block is pushed horizontally with just enough force to start its motion Accross a floor and the same force acts on it afterwards.The coefficient of static and sliding frictions are 0.5 and 0.4 respectively.

Find acceleration of the body.

Options

6m/s^2

4.9m/s^2

3.92m/s^2

1m/s^2

## Homework Equations

F= ma

Friction = (u)m.a where " u " is coefficient of friction

## The Attempt at a Solution

First I assumed that the total force need would be the summation of all the friction forces acting on the body

So I did

m.a = friction static + friction kinetic

60. a = 540

a = 9 m/s^2

But alas tis the wrong answer.

Then I tried another method which is in the attachment above I hope it is visible. ....but I'm pretty sure it's wrong.

[So don't delete the post oh ,moderator supreme overlord for I have tried !!!]

I would really like to know how to approach this problem

THIS IS ALL THE INFO GIVEN