When a hot milk is shaken in a thermoflask whose lid is closed. The temperature of the milk will
remain the same.
When a hot milk is shaken in a thermoflask whose lid is closed, the temperature of the milk will decrease. Here is a step-by-step explanation:
1. Initially, the hot milk in the thermoflask is at a certain temperature above room temperature. Let's say it is around 60 degrees Celsius.
2. When you shake the thermoflask, the milk inside experiences increased movement and agitation. This agitation promotes heat transfer.
3. As the milk gets agitated, it comes in contact with the inner walls of the thermoflask more frequently, allowing heat transfer to occur between the milk and the flask's walls.
4. The thermoflask, made of insulating material, is designed to minimize heat exchange with the surroundings. This means that the heat from the milk cannot easily escape to the external environment.
5. However, the agitation caused by shaking still allows a certain amount of heat to be transferred from the milk to the flask's walls. This heat transfer leads to a gradual reduction in the milk's temperature.
6. As you continue to shake the thermoflask, the milk's temperature will gradually decrease over time.
7. Eventually, if you shake it for long enough, the milk's temperature will approach the temperature of the surrounding environment, usually room temperature.