Question

A student is asked to determine the work done on a block of wood when the block is pulled horizontally using an attached string. The student is supplied with a spring scale, a stopwatch, and a meterstick. Which of the following graphical analysis techniques will allow the student to determine the work done on the block by the string?
A. Graphing the force as a function of time and calculating the slope
B. Graphing the force as a function of time and calculating the area under the curve
C. Graphing the force as a function of distance and calculating the slope
D. Graphing the force as a function of distance and calculating the area under the curve

Answer 1

Answer:

D. Graphing the force as a function of distance and calculating the area under the curve.

Explanation:

Answer 2

Answer:

The correct option is (D). "Graphing the force as a function of distance and calculating the area under the curve"

Explanation:

1) As we know from the definition of Work done which is Work = Force × Displacement. Time doesn't have any use in the mentioned equation and thus the stop watch is of no use to us.

2) Using the meter stick, we can measure the distance for which the block is pulled horizontally i.e "Displacement"

3) Using the spring scale, we can calculate the "Force" applied on the block of wood to move it horizontally.

4) For example, lets say that for a constant force of 4 Newtons, the wooden block is pulled horizontally 4 meters. Plotting Force vs Displacement on a graph would yield a horizontal line as shown in the attachment. Area under the F vs D graph will give us the total work done.