In a circuit with a thermistor and bulb, what happens to the brightness of the bulb as the temperature increases?

As the temperature increases, the resistance of the thermistor decreases. So the resistance of the whole circuit decreases. Using V=IR, the PD remains constant but resistance has decreased, so current must increase. Using V=IR in just the bulb, the resistance is unchanged, the current has increased so the PD increases. The bulb gets brighter

Related Physics A Level answers

All answers ▸

Why does light change direction when it hits a surface with a different refractive index?


From the 2016 OCR B paper A ball is thrown at an angle of 30 Degrees to the horizontal. The initial kinetic energy of the ball is K. Air resistance is negligible. What is the kinetic energy of the ball at the maximum height.


A man weighing 600N steps on a scale that contains a spring. The spring is compressed 1cm under their weight. Find the force constant of the spring and total work done on its compression.


State assumptions made about the motion of the molecules in a gas in the derivation of the kinetic theory of gases equation.