Simple Pressure Ballet dancer Problem

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The discussion centers on calculating the pressure exerted by a ballet dancer standing on her toes, first when stationary and then when leaping with acceleration. The correct area of contact is clarified as 26 cm², which converts to 0.0026 m², not 0.26 m². For part (a), the force is calculated using the dancer's weight, leading to a pressure of 1.88 x 10^5 Pa. For part (b), the total force includes the additional acceleration, resulting in a pressure of 2.65 x 10^5 Pa. The thread highlights the importance of accurate unit conversion and careful calculations in physics problems.
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Homework Statement


A 50kg ballet dancer stands on her toes during a performance with four square inches (26cm^2) in contact with the floor. What is the pressure exerted by the floor over the area of contact? (a) if the dancer is stationary and (b) if the dancer leaps upwards with an acceleration of 4m/s^2?


Homework Equations



26cm^2=.26m^2
P=F/A
F=mg

The Attempt at a Solution



For question (a) i got the force to be 50(9.8)=490N, then i divided that by .26m^2. I keep getting an incorrect answer. what am i doing wrong? Also, are there any suggestions on how to set up part (b)?


I know the answers are: (a) 1.88X10^5Pa, (b)2.65X10^5Pa
thank you
 
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1cm^2=10^-4 m^2
 
26cm^2=.26m^2. This is wrong.
26cm^2=26*10^-4m^2.
In part B force = 50*(9.8 + 4 ) N
 
Thanks to both of you. What careless errors on my part. :(
 

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