Identify the following scenarios as being either
examples or a non-examples of work. For each which are
non-examples, explain why it is not an example of work.
1. A teacher pushes against a wall for 5 minutes and
2. A group of teenagers push upon a car to move it out
of a ditch during a snowstorm.
3. Superman pushes upon truck to prevent it from
rolling down a hill.
The work done on an object is calculated using
Work = F d dosine (theta)
For each of the following situations, identify the
value of theta in the
1. A 12-N force is applied to a cart in a direction
parallel to the inclined plane in order to move the cart
from the floor 2.0 meters along the incline to the top of
a lab bench. The incline makes an angle of 30-degrees
with the horizontal.
2. A student exerts a 39.2-N uopward force on a 4.0-kg
suitcase as he walks a distance of 80-meters along a
horizontal walkway at an airport.
3. Fido has the hots for Fidella. So when Mr.
Jones takes a Fido for a walk around the block, he must
be careful to restrain Fido when walking by Fidella's
house. One day, Mr. Jones pulls upward and rightward at
an angle of 30 degrees with the horizontal to pull Fido
rightwards a distance of 1.2 meters.
4. A leftward friction force of 8200 N acts upon a
920-kg rightward moving car as it skids to a stop over a
distance of 26.0 meters.