(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

An object is free to move on a table, ex-

cept that there is a constant friction force f

that opposes the motion of the object when

it moves. If a force of 10 N pulls the object

across the table, the acceleration is 2 m/s2. If

a force of 20 N pulls the object across the ta-

ble, the acceleration is 6 m/s2. What is the

force of friction f?

a) 3.33 N

b) 1 N

c) 5 N

d) 10 N

e) none of these

2. Relevant equations

F= ma

and

F= -F'

and

F= μS where μ= coefficient of static friction

3. The attempt at a solution

i first find the mass in both case

F= 10 N and a= 2m/s/s

so

m= F/a = 10/2

m= 5kg

and again

F= 20N and a= 6m/s/s

so

m= F/a = 20/6

m= 3.33kg

what i do next..

or

either i must go to

F= μ S

please help me to solve it.. how i go further?

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# Homework Help: Newton's Third law of motion problem.

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