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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
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