The temperature of a coil cannot be measured by a Calorimeter.

Explanation:
A calorimeter is a device used to measure the amount of heat released or absorbed during a chemical or physical process. It works based on the principle of heat transfer, where the heat exchanged between the coil and its surroundings is measured.

However, in the given options, the temperature of a coil can be measured using other methods such as a thermometer, increase in resistance of the coil, and thermo-junctions embedded in the coil.

1. Thermometer:
A thermometer is a device used to measure temperature. It consists of a temperature-sensitive element, such as a bulb filled with a liquid or a thermocouple, which responds to changes in temperature. By placing a thermometer in close proximity to the coil, the temperature of the coil can be measured.

2. Increase in Resistance of the Coil:
The resistance of a metal coil is directly proportional to its temperature. As the temperature of the coil increases, the resistance also increases. This relationship is described by the temperature coefficient of resistance (TCR). By measuring the resistance of the coil using a suitable measurement device, such as a multimeter, the temperature of the coil can be inferred.

3. Thermo-Junctions Embedded in the Coil:
A thermo-junction, also known as a thermocouple, is a device that consists of two dissimilar metals joined together at one end. When there is a temperature difference between the two ends of the thermocouple, a voltage is generated, which is proportional to the temperature difference. By embedding thermocouples in the coil at different locations, the temperature distribution along the coil can be measured.

4. Calorimeter:
A calorimeter measures the heat exchanged between a system and its surroundings. It is not suitable for directly measuring the temperature of a coil because it does not provide a direct reading of the temperature. Instead, it measures the heat transfer associated with temperature changes. Therefore, a calorimeter cannot be used to measure the temperature of a coil directly.

In conclusion, the temperature of a coil cannot be measured using a calorimeter. Other methods such as a thermometer, increase in resistance of the coil, and thermo-junctions embedded in the coil can be used for temperature measurement.