Work Assignment

A tugboat pulls a ship with a constant force of 5000 N, causing the ship to move through a harbor. How much work does the tugboat do on the ship if each moves a distance of 3 km?

Answer:
W= F x D

= 5000 N x 3000 m

= 15 000 000 J

= 15 MJ

A husky dog does 20 kJ of work as he pulls a sleigh with a force of 340 N. Through what distance does he pull it?

Answer:

W= F x D

W = 20 000 = 340 x D

D = 20.000/ 340

= 58.8 m

What is the weight of a mass of 100 kg? Find the work done in raising a mass of 100 kg through a vertical height of 60 m.

Answer:

W = F x D

= 1000 x 60

= 60 000 J

= 60 KJ

Carlos does a chin-up in gym class and raises himself 0.8 m. If Carlos has a mass of 62 kg, how much work does he accomplish?

Answer:

W = F x D

= 620 x 0.8

= 490 J

A girl pushes her little brother on his sled with a force of 300 N for 750. m. How much work is this if the force of friction acting on the sled is (a) 200 N, (b) 300 N?

Answer:

a. W= (F1-F2) x D

    = (300 – 200) x 750

    = 75 000 J

    = 75 KJ

b. W= (F1-F2) x D

    = (300-300) x 750

    = 0