15 points for 2 questions 1. your family is moving to a new home. while lifting a box 1.5m straight up to put it on a truck, you exert an upward force of 200n. calculate the amount of work you did. a) 133j b) 198.5j c) 201.5j d) 300j 2. a truck pulls a trailer at a constant velocity for a 100m while exerting a force of 480n. calculate the work done. a) 4.8j b) 380j c) 48,000j d) 580j

1. D) 300 J

The work done by a constant force is given by:

where F is the force applied, d is the distance, and is the angle between the direction of the force and the direction of motion.

In this problem, F=200 N, d=1.5 m while , because the force is parallel to the motion of the box, therefore the work done is

2. C) 48,000 J

We can use the same formula used in the previous part of the problem:

In this case:

F=480 N

d=100 m

So the work done is

another example of kinetic energy would be,

kinetic energy   >     moving energy

answer   >   letter choice (c),   a hammer falling off a table.

hope that !                                         : )