Unformatted text preview: This is really handy for doing calculations of work if the force is not constant. • As long as we can calculate the area under the line, we will have the work that has been done. • Watch out that you use the appropriate area formula for the graph you are looking at. • We can not just run in and use the formula W = F d in these situations since force is not a constant. Example 1 : A rocket engine is going through a series of tests. It is ignited and data is measured as it builds up thrust. If the initial force was zero as it was switched on, and it increases constantly up to 1.6 e5 N as the rocket moves 112 m along the test track, determine how much work was done. First, we’ll graph the information (shown at right). Second, we calculate the area under the line (which is a basic triangle) to find out how much work was done. A = ½ b ( h ) = ½ 112m ( 1.6e5N ) = 9.0e6 J = W 10/21/2005 © studyphysics.ca Page 1 of 1...
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 Fall '08
 RABE
 Physics, Work, Rectangle

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