Concept explainers
(a)
The mass of the ice that melts.
(a)
Answer to Problem 20.76AP
The mass of the ice that melts is
Explanation of Solution
Given info: The mass of the copper block is
Write the expression for the change in kinetic energy of the block.
Here,
Substitute
Thus, the change in kinetic energy of the block is
Write the expression for the change in internal energy.
Here,
Substitute
Write the expression for the conservation of energy for the isolated copper ice system.
Here,
Substitute
Conclusion:
Therefore, the mass of the ice that melts is
(b)
The input energy, the change in internal energy and the change in mechanical energy for the block-ice system.
(b)
Answer to Problem 20.76AP
The input energy is
Explanation of Solution
Given info: The mass of the copper block is
The temperature of the air is
Write the expression for the change in mechanical energy of the block.
From part (a), change in kinetic energy of the block is
Substitute
Conclusion:
Therefore, the input energy is
(c)
The input energy and the change in internal energy for the ice as a system.
(c)
Answer to Problem 20.76AP
The input energy is
Explanation of Solution
Given info: The mass of the copper block is
The temperature of the ice is
From equation (1), the expression for the change in internal energy.
From part (a), the mass of the ice that melts is
Substitute
Conclusion:
Therefore, the input energy is
(d)
The mass of the ice that melts.
(d)
Answer to Problem 20.76AP
The mass of the ice that melts is
Explanation of Solution
Given info: The mass of the copper block is
Write the expression for the change in kinetic energy of the block.
Here,
Substitute
Thus, the change in kinetic energy of the block is
Write the expression for the change in internal energy.
Here,
Substitute
Write the expression for the conservation of energy for the isolated copper ice system.
Here,
Substitute
Conclusion:
Therefore, the mass of the ice that melts is
(e)
The input energy and the change in internal energy for the block of ice as a system and
(e)
Answer to Problem 20.76AP
The input energy is
Explanation of Solution
Given info: The mass of the copper block is
The temperature of the block of the ice is
From equation (1), the expression for the change in internal energy.
From part (a), the mass of the ice that melts is
Substitute
Thus, the change in internal energy for the block of ice as a system is
Write the expression for the change in mechanical energy for the block-ice system.
From part (a), change in kinetic energy of the block is
Substitute
Conclusion:
Therefore, the input energy is
(f)
The input energy and the change in internal energy for the metal sheet as a system.
(f)
Answer to Problem 20.76AP
The input energy for the metal sheet as a system is
Explanation of Solution
Given info: The mass of the copper block is
The temperature of the metal sheet is
Conclusion:
Therefore, the input energy for the metal sheet as a system is
(g)
The change in temperature of both objects.
(g)
Answer to Problem 20.76AP
The change in temperature of both objects is
Explanation of Solution
Given info: The mass of the copper slab is
Write the expression for the change in kinetic energy of the copper slab.
Here,
Substitute
Thus, the change in kinetic energy of the copper slab is
Write the expression for the change in internal energy.
Substitute
Thus, the change in internal energy of the copper slab is
Write the expression for the change in internal energy due to the temperature change.
Here,
Substitute
Conclusion:
Therefore, the change in temperature of both objects is
(i)
The input energy and the change in internal energy for the stationary slab.
(i)
Answer to Problem 20.76AP
The input energy is
Explanation of Solution
Given info: The mass of the copper slab is
The temperature of the stationary slab is
Conclusion:
Therefore, the input energy is
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Chapter 20 Solutions
PHYSICS 1250 PACKAGE >CI<
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