Manual Testing Interview Question:

Consider the cold storage house, which has two rooms to store and preserve different edible products. in the first room the temperature to be maintained is between 1 to – 4 degree centigrade. in the other room the temperature to be maintained is between 1 to 5 degree centigrade. thermometers and freezers are attached in the room to maintain the required temperature. the thermometer notifies the temperature after every 5 min to the electronic circuitry, which decides if the freezer needs to be started. once the freezer starts it works till minimum temperature required is reached and then the circuitry switches the freezer off. the tolerance of the circuitry is +5% (i.e.) the circuitry doesn't take any action if the noted temperature is 5 % more or less than the temperature range to be maintained.
write the test case to check the implementation of the system assuming that there is no time delay it the thermometer sensing the temperature, notifying it to the circuitry, and the circuitry actually switching on the freezer?