Find the work done by nonconservative forces in stopping the plane.

AI Thread Summary
The discussion focuses on calculating the work done by nonconservative forces in stopping an 18,000 kg airplane landing at 92 m/s on a 115 m long aircraft carrier deck. The initial calculation attempted was 18000 * 92 * 115, yielding 190,440,000 J, but this was deemed incorrect due to potential loss of significant digits. The correct approach involves using energy considerations, specifically the kinetic energy formula, leading to a final answer of -7.6 x 10^7 J. The units for the work done are confirmed to be in joules, indicating the energy lost during the stopping process.
stuckne1
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Homework Statement


Find the work done by nonconservative forces in stopping the plane.

A 18000 {\rm kg} airplane lands with a speed of 92 {\rm m/s} on a stationary aircraft carrier deck that is 115 {\rm m} long.


Homework Equations


W = FD


The Attempt at a Solution



18000 * 92 * 115 = 190440000 J

Unless it's wanting 1.9 * 10^8 = 190000000 J (which seems wrong since detail is lost)

(I don't think that's 2 significant digits.)
 
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stuckne1 said:

Homework Statement


Find the work done by nonconservative forces in stopping the plane.

A 18000 {\rm kg} airplane lands with a speed of 92 {\rm m/s} on a stationary aircraft carrier deck that is 115 {\rm m} long.


Homework Equations


W = FD


The Attempt at a Solution



18000 * 92 * 115 = 190440000 J

Unless it's wanting 1.9 * 10^8 = 190000000 J (which seems wrong since detail is lost)

(I don't think that's 2 significant digits.)

The best way to solve this type of problem is with energy considerations. What was the KE of the plane just before it traps on the carrier deck? What is the KE right after it is stopped by the wire? Wher did that energy go?
 
it was 1/2(m)(v)^2 or something.

The answer was -7.6 x 10 ^7

Thanks!
 
stuckne1 said:
it was 1/2(m)(v)^2 or something.

The answer was -7.6 x 10 ^7

Thanks!

Does that mean that you calculated the correct answer? What are the units of the answer?
 
Yes, the units of the correct answer was in joules.
 
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