Electronics Quiz

Answer: Limit the flow of electric current in a circuit. A resistor opposes the flow of current, which limits intensity, protects components, or divides voltage within a circuit.

Answer: Printed Circuit Board. A PCB is an insulating board on which conductive copper traces connect electronic components to one another.

Answer: To display the shape of an electrical signal over time. An oscilloscope graphically displays how a voltage changes over time, allowing the shape, frequency, and amplitude of a signal to be observed.

Answer: Its value in ohms and its tolerance. A standardized code of colored bands, each corresponding to a digit or a multiplier, allows a resistor's value in ohms and its tolerance to be read directly, without a measuring instrument.

Answer: Analog varies continuously, digital by discrete values (0 and 1). An analog signal varies continuously (like the sound of a voice), while a digital signal only takes discrete values, usually represented as 0s and 1s.

Answer: From the silicon used in the microchips made there. The phrase was popularised in 1971 by a journalist. The region then had many semiconductor makers, whose descendants are today's digital giants.

Answer: High-Definition Multimedia Interface. Launched in 2002, it carries both picture and sound digitally in a single cable. It replaced the SCART plug, a source of pride for 1970s French engineering.

Answer: By induction, through a magnetic field between two coils. A coil in the pad creates a changing magnetic field that induces a current in a coil inside the phone. It is the same principle as induction hobs and electric toothbrushes.

Answer: Resolution, in dots per inch. The more dots per inch, the finer the image. 300 dpi is often considered "photo" quality in print.

Answer: Store energy in the form of a magnetic field. A coil (or inductor) stores energy in a magnetic field created by the flow of current, and opposes sudden changes in that current.

Answer: The vacuum tube (triode). Lee de Forest's triode was the first component capable of amplifying an electrical signal, a key advance that made radio, television, and early computers possible.

Answer: Package formats for integrated circuits. BGA (Ball Grid Array) places connections as solder balls under the package, while QFN (Quad Flat No-lead) uses flat contacts with no protruding pins; these compact formats allow high integration density.

Answer: To test a board's electrical connections without physical access to each pin. JTAG testing (IEEE 1149.1 standard) allows electrical connections to be checked and certain components to be programmed through a standardized interface, without needing physical probes on every pin of the circuit.

Answer: To strongly and precisely amplify very weak electrical signals. The operational amplifier is a versatile component capable of amplifying signals with very high, precise gain, widely used in filters, sensors, and signal processing circuits.

Answer: Using a piezoelectric crystal that creates a voltage when pressed. Some crystals, such as quartz, produce a voltage when squeezed. The same principle powers some microphones and sensors.

Answer: The Peltier effect. Discovered in 1834 by Frenchman Jean Peltier, it is used in electric cool boxes and to cool some processors. With no moving parts, it is silent but not very efficient.

Answer: Blue. Without the blue LED, white LED light was impossible. It paved the way for low-energy bulbs and modern screens.