Question

Because the snow suddenly gets too slushy, you decide to carry your 100-n sled the rest of the way home. How much work do you do when you pick up the sled, lifting it 0.5 m upward? how much work do you do to carry the sled if your if your house is 800 m away?

Answer 1

 Work  =  (weight) x (distance lifted)

           =  (100 N)  x  (0.5 m)

           =       50 joules.


If you carry the sled level all the way to your house, you're not moving it
against gravity. 

Although you're huffing and puffing and sweating by the time you reach
your house, still, according to the Physics definition of work, you have
done NO work on the sled all the way home.