Concept explainers
The ratio of the weight of the twin in the boat to the weight of his brother on solid ground.
Answer to Problem 74P
The ratio of the weight of the twin in the boat to the weight of his brother on solid ground is
Explanation of Solution
Write the expression for the density of the lake.
Here,
Write the expression for the density of Earth.
Here,
Write the expression for the force due to lake on the twin.
Here,
Write the expression for the force due to Earth on the twin.
Here,
Use equation (II) and (I) to solve for the ratio of force of gravity due to the lake on the twin to the Earth acting on the twin.
Use equation (V) to solve for the
Write the expression for
Here,
Use equation (VII) to write the expression for the
Use equation (VIII) in (I) to solve for
Use equation (IX) and (VII) in (IV) to solve for
Write the expression for the difference in the force due to Earth to the lake acting on the twins.
Here,
Write the expression for the ratio of total weight experienced by the twins.
Use equation (XI) in (XII) to solve for
Conclusion:
Substitute
Substitute
Substitute
Therefore, the ratio of the weight of the twin in the boat to the weight of his brother on solid ground is
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Chapter 5 Solutions
College Physics, Volume 1
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