Thermometers

firstly, the heat causes the liquid to expand. As it begins to expand it rises up the tube.

This process occurs through conduction.

• - portable
• - cheap
• - does not require batteries
• - easy to clean
• - does not require medical training

• - it could break and cause damage to the patient.
• - it's not very precise
• - human error (can be misread easily)

• For thermistors to work a resistance is needed in an electrical circuit for the temperature to take affect.
• As the temperature increases the resistance decreases.
• The greater the change in temperature the greater the change in resistance.
• the digital reading for the temperature is then calibrated against the resistance.

• More accuracy (less chance of human error)
• Readings appear automatically
• readings can be stored
• more sensitive so it can sense a slight change in temperature.

• can run out of batteries
• too sensitive and external surroundings can affect the temperature measured.
• non invasive

• it works through the process of conduction.
• the strip changes colour dependant on the temperature of the patient.

• - does not require batteries
• - no medical training
• - easy to read

• - it's not very accurate
• - readings cannot be taken automatically
• - human error ( scale can be misread)