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| 1 | |
The interaction that occurs between a system and its surroundings as the system executes a process, which is the result of the system being at a temperature different from the surroundings, is: |
| | A) | Mass transfer |
| | B) | Heat transfer |
| | C) | Work transfer |
| | D) | None of these |
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| 2 | |
Which one of the equations below serves to define work? |
| | A) |  <![CDATA[<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif::::/sites/dl/free/0073398179/22358/A3_2a.gif','popWin', 'width=133,height=100,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a>]]> |
| | B) |  <![CDATA[<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif::::/sites/dl/free/0073398179/22358/A3_2b.gif','popWin', 'width=150,height=116,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a>]]> |
| | C) |  <![CDATA[<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif::::/sites/dl/free/0073398179/22358/A3_2c.gif','popWin', 'width=156,height=116,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a>]]> |
| | D) |  <![CDATA[<a onClick="window.open('/olcweb/cgi/pluginpop.cgi?it=gif::::/sites/dl/free/0073398179/22358/A3_2d.gif','popWin', 'width=143,height=116,resizable,scrollbars');" href="#"><img valign="absmiddle" height="16" width="16" border="0" src="/olcweb/styles/shared/linkicons/image.gif"> (0.0K)</a>]]> |
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| 3 | |
A 1000 kg automobile accelerates from 10 km/hr to 120 km/hr. How much work does this require? |
| | A) | 0 kJ |
| | B) | 501 kJ |
| | C) | 552 kJ |
| | D) | 780 kJ |
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| 4 | |
A 12 V DC electrical motor draws a current of 18 amps. How much work does this motor produce over a 10-minute period of operation? |
| | A) | 97.42 kJ |
| | B) | 129.6 kJ |
| | C) | 216.0 kJ |
| | D) | 318.2 kJ |
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| 5 | |
Which one is NOT part of the total energy of a system? |
| | A) | Sensible energy |
| | B) | Chemical energy |
| | C) | Work |
| | D) | Thermal energy |
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| 6 | |
A fluid is accelerated from a zero velocity to 44.7 m/s. The change in the kinetic energy of the fluid is |
| | A) | 2000 kJ/kg |
| | B) | 1000 kJ/kg |
| | C) | 2 kJ/kg |
| | D) | 1 kJ/kg |
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| 7 | |
A cold soda initially at 2ºC gains 18 kJ of heat in a room at 20ºC during a 15-min period. What is the average rate of heat transfer during this process? |
| | A) | 20 W |
| | B) | 18 W |
| | C) | 12 W |
| | D) | 10 W |
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| 8 | |
The air contained in a room loses heat to the surroundings at a rate of 50 kJ/min while work is supplied to the room by computer, TV, and lights at a rate of 1.2 kW. What is the net amount of energy change of the air in the room during a 30-min period? |
| | A) | 0.36 kJ |
| | B) | 70 kJ |
| | C) | 660 kJ |
| | D) | 1100 kJ |
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| 9 | |
A 40-kg rock is dropped from an elevation of 10 m. What is the velocity of the rock when it is 5-m from the ground? |
| | A) | 2.0 m/s |
| | B) | 3.9 m/s |
| | C) | 7.0 m/s |
| | D) | 9.9 m/s |
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| 10 | |
A car engine produces an average of 25 kW of power in a period of 10-min during which 1.25 kg of gasoline is consumed. If the heating value of gasoline is 43,000 kJ/kg, the efficiency of this engine during this operation is |
| | A) | 24% |
| | B) | 28% |
| | C) | 32% |
| | D) | 36% |
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