(a)
Work done by the assistant for the football team in carrying a 30.0 kg cooler from the top row of the stadium to the bench area located 20.0 m below.
Answer to Problem 42QAP
The work done by the assistant for the football team in carrying a 30.0 kg cooler from the top row of the stadium to the bench area located 20.0 m below is
Explanation of Solution
Given:
Mass of the cooler
Vertical displacement of the cooler
Acceleration due to gravity
Formula used:
The work done W by a force
Calculation:
The weight
Write an expression for
Therefore,
Write an expression for the work done by the force exerted by the assistant.
Calculate the work done by substituting the known values in the above equation.
Conclusion:
Thus, the work done by the assistant for the football team in carrying a 30.0 kg cooler from the top row of the stadium to the bench area located 20.0 m below is
(b)
The work done by the gravity on the cooler.
Answer to Problem 42QAP
The work done by the gravity on the cooler is
Explanation of Solution
Given:
Mass of the cooler
Vertical displacement of the cooler
Acceleration due to gravity
Formula used:
The work done W by a force
Calculation:
Write an expression for the work done by gravitational force.
Substitute the known values of the variables in the expression.
Since the displacement is in the direction of the force, the work done is positive.
Conclusion:
Thus, the work done by the gravity on the cooler is
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Chapter 6 Solutions
COLLEGE PHYSICS
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