Question
________ is an invisible transfer of energy into or out of a system.
- Heat
- Light
- Work
- Pressure
Hint:
Heat is an extensive property, and is proportional to the total energy of all atoms in an object. Temperature, on the other hand, is an intensive property, as it is proportional to the average energy per atom.
The correct answer is: Heat
Heat: It may be defined as the invisible form of energy that causes a sensation of hotness and coldness. For example, when we hold a hot cup of tea in our hands we feel heat energy. Heat energy always flows from a hot object to a cold object.
Related Questions to study
Heat is added or removed from a system by _____.
Heat is added or removed from a system by _____.
When the system is touched to a hot reservoir its internal energy _____.
When the system is touched to a hot reservoir its internal energy _____.
When the work is done on the system its internal energy _____.
When the work is done on the system its internal energy _____.
Two systems in contact are in thermal equilibrium. This means that ____.
Two systems in contact are in thermal equilibrium. This means that ____.
Work is done on or by the particles of a gas system by _____.
Work is done on or by the particles of a gas system by _____.
_____ is a visible transfer of energy into or out of a system.
_____ is a visible transfer of energy into or out of a system.
The volume of the system does not change. Such a system is called ____.
The volume of the system does not change. Such a system is called ____.
The temperature of the system does not change. Such a system is called ________.
The temperature of the system does not change. Such a system is called ________.
A pot of water is heated, what happens at a molecular level?
A pot of water is heated, what happens at a molecular level?
743 J = ____ cal
743 J = ____ cal
847 cal = ___ kcal
847 cal = ___ kcal
625 cal = ____ J
Energy is the ability to do work which is measured in different units. Calorie and Joule are the units of energy which are proportionate to each other. This implies any change in the value of calories will change its equivalent value in joules. The relation between calorie and joule can be numerically written as : 1 calorie = 4.2 joules approx.
Hence, 625 cal= (625* 4.2)= 2,615 joules.
625 cal = ____ J
Energy is the ability to do work which is measured in different units. Calorie and Joule are the units of energy which are proportionate to each other. This implies any change in the value of calories will change its equivalent value in joules. The relation between calorie and joule can be numerically written as : 1 calorie = 4.2 joules approx.
Hence, 625 cal= (625* 4.2)= 2,615 joules.
25 kcal = ____cal
The kilo calorie is a measurement unit of energy. The symbol of kilo calorie is kcal.The kilocalorie is used in measuring the heating, calorific value or metabolizing foods. It equals to 1000 calories, or approximately 4.2 kilojoules. Therefore, 1 kcal= 1000 cal.
so, 25 kcal= (25*1000)= 25000 cal.
25 kcal = ____cal
The kilo calorie is a measurement unit of energy. The symbol of kilo calorie is kcal.The kilocalorie is used in measuring the heating, calorific value or metabolizing foods. It equals to 1000 calories, or approximately 4.2 kilojoules. Therefore, 1 kcal= 1000 cal.
so, 25 kcal= (25*1000)= 25000 cal.
When sufficient heat is supplied to an ice cube
When heat is applied to an ice molecule, the solid phase changes to the liquid phase and thus the ice is melted into water after applying heat. Heating a substance makes the molecules move faster and thus the heat energy breaks the hydrogen bonds that hold the molecules in the ice together thus resulting in melting of ice.
When sufficient heat is supplied to an ice cube
When heat is applied to an ice molecule, the solid phase changes to the liquid phase and thus the ice is melted into water after applying heat. Heating a substance makes the molecules move faster and thus the heat energy breaks the hydrogen bonds that hold the molecules in the ice together thus resulting in melting of ice.
Match the following:
| State | Flow of heat | ||
| a |  |
i | To the hand |
| b |  |
ii | From the hand |
| c |  |
iii | None |
Match the following:
| State | Flow of heat | ||
| a | |
i | To the hand |
| b | |
ii | From the hand |
| c | |
iii | None |
