# Tension force in a tow truck

## Homework Statement

A tow truck drags a stalled car along a road. The chain makes an angle of 30° with the road and the tension in the chain is 1500 N. How much work is done by the truck in pulling the car 1 km?

## Homework Equations

Work = Force * distance

## The Attempt at a Solution

By drawing a free body diagram, I learn that the horizontal component of tension is 1500 * cos(30), which is apprx 1300 N. I then multiply by 1000 meters to get 1.3 million joules. Is this correct? Is joules always measured in meters or should I have multiplied by 1 instead? Thank You

I put this question in math because it's from my Multivariate Calculus Late Transcendentalist book.

SammyS
Staff Emeritus
Homework Helper
Gold Member
... Is joules always measured in meters or should I have multiplied by 1 instead? Thank You[/QUOTE]

##1 \text{Joule} =1 \text{N}\cdot\text{m }, ## so Joules are not in units of meters.

• 299
haruspex
Homework Helper
Gold Member

## Homework Statement

A tow truck drags a stalled car along a road. The chain makes an angle of 30° with the road and the tension in the chain is 1500 N. How much work is done by the truck in pulling the car 1 km?

## Homework Equations

Work = Force * distance

## The Attempt at a Solution

By drawing a free body diagram, I learn that the horizontal component of tension is 1500 * cos(30), which is apprx 1300 N. I then multiply by 1000 meters to get 1.3 million joules. Is this correct? Is joules always measured in meters or should I have multiplied by 1 instead? Thank You
• Looks right. 1 J = 1 N m