Concept explainers
(a)
Find the mass of the ice that melts.
(a)
Answer to Problem 76AP
The mass of the ice that melts is
Explanation of Solution
Write the equation for kinetic energy,
Here,
Write the appropriate energy equation for isolated copper ice system.
Here,
Conclusion:
Substitute
Therefore, the mass of the ice that melts is
(b)
Find the energy input, change in internal energy and change in the mechanical energy of the block-ice system.
(b)
Answer to Problem 76AP
The general continuity equation for energy is,
The energy input, change in internal energy and change in the mechanical energy of the block-ice system are
Explanation of Solution
For the block as a system
Conclusion:
For the block-ice system.
Therefore, the energy input, change in internal energy and change in the mechanical energy of the block-ice system are
(c)
Find the energy input and change in internal energy for the ice system.
(c)
Answer to Problem 76AP
The energy input and change in internal energy for the ice system are
Explanation of Solution
For the ice as a system
Conclusion:
For the ice system.
Therefore, the energy input and change in internal energy for the ice system are
(d)
Find the mass of the ice that melts.
(d)
Answer to Problem 76AP
The mass of the ice that melts is
Explanation of Solution
This is same as solved in part a, use the equations in part a.
Conclusion:
Substitute
Therefore, the mass of the ice that melts is
(e)
Find the energy input, change in internal energy for the ice system and change in mechanical energy for the block-ice system.
(e)
Answer to Problem 76AP
The energy input, change in internal energy for the ice system and change in mechanical energy for the block-ice system are
Explanation of Solution
For the ice as a system
Conclusion:
For the ice system.
For block-ice system
Therefore, the energy input, change in internal energy for the ice system and change in mechanical energy for the block-ice system are
(f)
Find the energy input and change in internal energy for the metal-sheet system.
(f)
Answer to Problem 76AP
The energy input and change in internal energy for the metal-sheet system are
Explanation of Solution
For the ice as a system
Conclusion:
For the metal sheet system,
Therefore, the energy input and change in internal energy for the metal-sheet system are
(g)
Find the change in the temperature.
(g)
Answer to Problem 76AP
The change in the temperature is
Explanation of Solution
Write the appropriate energy equation for copper-copper system.
As the system have symmetry, each of the copper slab possesses half of the internal energy change of the system.
Then, the internal energy change of the copper slab is,
Conclusion:
Substitute
Therefore, the change in the temperature is
(h)
Find the energy input, change in internal energy for the sliding slab and change in mechanical energy for the two-slab system.
(h)
Answer to Problem 76AP
The energy input, change in internal energy for the sliding slab and change in mechanical energy for the two-slab system are
Explanation of Solution
For the sliding slab
Conclusion:
For two-slab system
Therefore, the energy input, change in internal energy for the sliding slab and change in mechanical energy for the two-slab system are
(i)
Find the energy input and change in internal energy for the stationary slab.
(i)
Answer to Problem 76AP
The energy input and change in internal energy for the stationary slab are
Explanation of Solution
For the stationary slab
Conclusion:
For stationary slab
Therefore, the energy input, change in internal energy for the sliding slab and change in mechanical energy for the two-slab system are
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Chapter 20 Solutions
Physics: for Science.. With Modern. -Update (Looseleaf)
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