# Frictional Force

• Jan 28th 2010, 01:32 PM
JM92
Frictional Force
Hi
A quick question i have some of you canhelp me with, i have sort of worked it out just need to see what everyone else got?
Question:
The frictional force F newtons and load L are connected by the law F = aL = b. When F = 6.0 N, L = 7.5N and when F =2.7N, L = 2.0N

What do you come up with?
thanks in advance for any help (Yes)
• Jan 28th 2010, 01:51 PM
masters
Quote:

Originally Posted by JM92
Hi
A quick question i have some of you canhelp me with, i have sort of worked it out just need to see what everyone else got?
Question:
The frictional force F newtons and load L are connected by the law F = aL = b. When F = 6.0 N, L = 7.5N and when F =2.7N, L = 2.0N

What do you come up with?
thanks in advance for any help (Yes)

Hi JM92,

I don't really see a question. Are you looking for the friction coefficient in each case?

I believe all you need to do is set up the formula:

$F=aL$

$6=a(7.5)$

$a=.8$

and solve for a.

Is that it?
• Jan 28th 2010, 02:01 PM
JM92
Sorry seems it hasnt posted all the question, i need to calculate the value of A and B.
• Jan 28th 2010, 02:14 PM
masters
Quote:

Originally Posted by JM92
Sorry seems it hasnt posted all the question, i need to calculate the value of A and B.

The way you've stated your formula 'F = b'. You already know F in each case. So, you also know b.

You said you 'sort of worked it out', so what did you come up with?
• Jan 28th 2010, 02:25 PM
JM92
Dont know how right this is but heres what i done:

F=aL=b

Therefore F=b=2.7N

aL=2.7N

a=2.7N/2.0N

a=1.35

if F=6 and L=7.5

b=6N and
a = 6/7.5 = 0.8

If thats incorrent can any one help me to get the value of A and B?
• Jan 29th 2010, 03:03 PM
BabyMilo
F = aL = b
do you mean F = aL + b