Eduqas GCSE Electronics switching and diodes overview quiz quiz

$0.3\ \text{V}$

$0.7\ \text{V}$

$2.0\ \text{V}$

$5.0\ \text{V}$

From cathode to anode

From anode to cathode (the way the triangle points)

In both directions equally

Only when reverse biased

To increase the coil current

To rectify the supply

To absorb the back-EMF when the current is switched off and protect the transistor

To make the relay switch faster

$0.9\ \text{mA}$

$9.0\ \text{mA}$

$0.09\ \text{mA}$

$90\ \text{mA}$

$2.5\ \text{k}\Omega$

$2.15\ \text{k}\Omega$

$2.85\ \text{k}\Omega$

$0.35\ \text{k}\Omega$

Cut-off

Saturation

Active (linear) region

Reverse bias

A current into the gate

A voltage on the gate

The temperature of the channel

The light falling on it

The MOSFET has a higher current gain

The MOSFET needs a gate voltage but essentially no steady gate current

The MOSFET runs on a lower supply voltage

The MOSFET does not need a load resistor

High

Low

Exactly half the supply

It varies smoothly with the difference

By the supply voltage alone

By a potential divider giving the reference, often with a variable resistor

By the gain of the sensor

By the load resistance

Opposes the change to stabilise the gain

Reinforces the change, giving a snap action (and can latch the output on)

Removes the need for a power supply

Converts a.c. to d.c.

Rectification

Chatter, the rapid on-off flicker when a noisy input hovers near a single threshold

The need for a reference voltage

Forward conduction of the diode