Question #e5993

1 Answer
Jun 15, 2015

The work done on the box is equal to 705 J.

Explanation:

They key to problems in which objects are being acted upon by a force at an angle with the horizontal is to realize that only the horizontal component of this force, i.e. the one parallel to the displacement, does the work.

http://www.mindset.co.za/resources//0000032945/0000040386/0000041483/SCIUNIT27_04.htm

Since no mention of friction is made, you can safely assume that the box has a frictionless motion. If you take #theta# to be the angle the force makes with the horizontal, then the horizontal component of the force will be

#F_x = F * cos(theta)#

This means that work, which is done everytime a force acts through a distance, will be equal to

#W = F_x * d = F * cos(theta) * d#

Plug in your values to get

#W = "75.0 N" * "10.0 m" * cos(20^@) = color(green)("705 J")#