# Find the Tension in the rope ( really simple )

1. Oct 27, 2008

### rulzwrld

Find the Tension in the rope ....( really simple :D)

1. The problem statement, all variables and given/known data
A block pulled by a string is moving on a horizontal plane with a constant speed, it weighs 25.0 N and its coefficient of kinetic friction is 0.35 . Find the tension in the rope ?

2. Relevant equations
Fx = t - Fk
T = Fk = μk * N = μk *mg

3. The attempt at a solution
My answer results 85.84 N ... which is completely off the textbook answer 8.75 which can be yield by μk * m ..... I dont understand why does it eliminate the 'g' out of the equation???

2. Oct 27, 2008

### heth

Re: Find the Tension in the rope ....( really simple :D)

Look at the units mentioned in the question.

3. Oct 27, 2008

### rulzwrld

Re: Find the Tension in the rope ....( really simple :D)

Lol , thanks, i actually came back coz i found the answer and I knew it was something really stupid ......

4. Oct 27, 2008

### heth

Re: Find the Tension in the rope ....( really simple :D)

No problem! Every year, the AP examiners' report mentions that many many points are lost because of units or calculation errors, so always check the units!