College Physics
1st Edition
ISBN: 9781938168000
Author: Paul Peter Urone, Roger Hinrichs
Publisher: OpenStax College
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Textbook Question
Chapter 9, Problem 39PE
Unreasonable Results
Suppose two children are using a uniform seesaw that is 3.00 m long and has its center of mass over the pivot. The first child has a mass of 30.0 kg and sits 1.40 m from the pivot. (a) Calculate where the second 18.0 kg child must sit to balance the seesaw. (b) What is unreasonable about the result? (c) Which premise is unreasonable, or which premises are inconsistent?
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A heavy boy and a light weight girl are balanced on a massless seesaw. If they both move forward so that they are one-half their original distance from the pivot point, what will happen to the seesaw?
a) It is impossible to say without knowing the masses.
b) It is impossible to say without knowing the distances.
c) The side the boy is sitting on will tilt downward.
d) Nothing, the seesaw will still be balanced.
e) The side the girl is sitting on will tilt downward.
2, A seesaw in a children’s playground is 4.00 m long pivoted at its center. Suppose a 25-kg child sits at one end of the board, where should a 35-kg child sit to balance the seesaw?
A seesaw with a length of 5 m and a mass of 40 kg is pivoted at its center. A 20kg
child sits on one end. (a)lf the parent pushes at a distance of 2m from the center,
what force should she exert to keep the seesaw level? (b) What will be the
answer in (a) if the weight of the seesaw is doubled?
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Chapter 9 Solutions
College Physics
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