Topic 14: Digital Technology

Question 1

Analogue technique

Answer 1

Involves codes and signal that can take a large number of different values between given limits.

Question 2

Analogue signal

Answer 2

Continuously varies with time

Question 3

Digital techniques

Answer 3

Involves codes and signals, as well as binary digits (bits). Each bit can take 2 values: High (1) and Low (0).

Question 4

Byte

Answer 4

8 bits

Question 5

Digital signal

Answer 5

Repeatedly changes between two available levels.

Question 6

Most significant digit

Answer 6

Binary digit on far left

Question 7

Least significant digit

Answer 7

Binary digit on far right

Question 8

Charge-coupled device (CCD)

Answer 8

Silicon (semiconductor) microchip that can be used to electronically record an image focused onto its surface. Surface divided into large number of small areas (pixels)

Question 9

Capacitor

Answer 9

Electrical component that stores charge (2 parallel plates separated by small air gap)

Question 10

Magnification on CCD

Answer 10

Length of image on CCD

Question 11

Resolution

Answer 11

Amount of detail an image contains

Question 12

Quantum efficiency

Answer 12

Ratio of number of electrons emitted on a CCD to number of photons incident.

Question 13

Magnification

Answer 13

Ratio of height of image and height of object

Question 14

Capacitance

Answer 14

C= q/V C is capacitance in farads (F), q is charge in coulombs, V is p.d. in volts