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Answer:
The answer an be the option A.
Explanation:
Because radioactive substances have atomic number greater than 82.
Answer:
D. A dry cell battery
Explanation:
A dry cell is a type of electric battery, commonly used for portable electrical devices. It was developed in 1886 by the German scientist Carl Gassner, after development of wet zinc-carbon batteries by Georges Leclanché in 1866.
Answer:
For the Carnot air conditioner working as a heat pump between 63 and 100°F , It would transfer 3.125 Joules of heat for each Joule of electric energy supplied.
Explanation:
The process described corresponds to a Carnot Heat Pump. A heat pump is a devices that moves heat from a low temperature source to a relative high temperature destination. <em>To accomplish this it requires to supply external work</em>.
For any heat pump, the coefficient of performance is a relationship between the heat that is moving to the work that is required to spend doing it<em>.</em>
For a Carnot Heat pump, its coefficient of performance is defined as:
Where:
- T is the temperature of each heat deposit.
- The subscript H refers to the high temperature sink(in this case the outdoors at 100°F)
- The subscript L refers to the low temperature source (the room at 63°F)
Then, for this Carnot heat pump:

So for each 3.125 Joules of heat to moved is is required to supply 1 Joule of work.
Earth is the center according to the geocentric model.