Calculating Work Done by Sled Dogs: A Frustrating Challenge!

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SUMMARY

The discussion focuses on calculating the work done by sled dogs dragging a 46.5 kg sled over a distance of 1.73 km with a coefficient of friction of 0.233. The correct approach involves using the formula for work, W = Fd, where the force must account for both the gravitational force and the frictional force acting against the sled. The frictional force is calculated as the product of the coefficient of friction and the normal force, which is equal to the weight of the sled. It is crucial to convert all units to the standard metric system for accurate calculations.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Familiarity with the concepts of work and energy
  • Knowledge of frictional forces and coefficients
  • Ability to perform unit conversions in physics calculations
NEXT STEPS
  • Calculate work done using W = Fd, incorporating frictional forces
  • Study the relationship between normal force and frictional force
  • Explore the implications of using standard metric units in physics
  • Review examples of work-energy principles in real-world scenarios
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in understanding the dynamics of work done by forces in mechanical systems.

kcrox
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Sled Dogs work?

A team of dogs drags a 46.5 kg sled 1.73 km over a horizontal surface at a constant speed. The coefficient of friction between the sled and the snow is 0.233. The acceleration of gravity is 9.8 m/s2 . Find the work done by the dogs. Answer in units of kJ


2. W=Fd
F=mg



3. I tried (46.5*9.8)1.73 it was wrong
(46.5*9.8)+(.233(46.5*9.8)) it was wrong

I desperately need help!
 
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Sled will move with uniform velocity , when the frictional force is balanced with the applied force.
 


You must take in consideration that the dogs are also overcoming the frictional force of the sled. You must subtract the work done by the frictional force, which would be negative as supported by intuition.

The coefficient of kinetic friction is NOT the frictional force by the way. The frictional force is equal to the coefficient times the normal force. Also, you might want to use standard mks units throughout the calculation. Meaning that instead of km, use meters.
 

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