Question

A thermos bottle containing coffee is vigorously shaken. If the coffee is considered as a system, then the temperature of the coffee will:
(A) increase slightly.
(B) fall.
(C) remain the same.
(D) can’t be determined.

Answer 1

Hint:The temperature of the coffee can be found out with the help of the law of thermodynamic systems. There are totally three types of thermodynamic systems, they are closed system, open system and isolated system. A thermodynamic system can go through an inner modification and interchange energy with the exterior environment.

Complete step-by-step solution:
A thermodynamic system can be explained as an amount of matter or a zone in space in which observation is targeted on the problem. Everything that is a part of the external of the system is known as the environment. The system is divided from the environment by the system boundary. The limitation of the system can be stable or movable.
The thermo flask or a bottle is an example of one of the thermodynamic systems, that is an isolated system. Isolated system is a type of thermodynamic system which does not allow the interchange of matter with the exterior environment and It do not permit the transmission of energy with the exterior environment. Since the thermos bottle is an example of an isolated system, when the bottle is aggressively shaken, the kinetic energy of the molecules in the coffee will be risen. Since the temperature is directly proportional to the kinetic energy of the molecule, the temperature of the coffee will be increased.
Therefore, when the thermos bottle containing coffee is vigorously shaken. If the coffee is considered as a system, then the temperature of the coffee will increase slightly.
Hence, the option (A) increases slightly is the correct answer.

Note:- The vacuum flask which is also referred to as the Dewar flask, is an enclosed deposited container that greatly extends the time over which its contents remain hotter or cooler than the flask's surroundings. It was Invented by Sir James Dewar.