A-LevelPhysicsElectricity9702/42 · May/June 2017 · Q56 Marks
State two advantages of the transmission of data in digital form rather than in analogue form. 1. ..................................................................................................................................................... 2. ..................................................................................................................................................... [2]
- (a)State two advantages of the transmission of data in digital form rather than in analogue form. 1. ..................................................................................................................................................... 2. ..................................................................................................................................................... [2][2]
- (b)(i)Outline the process by which the ADC converts the analogue signal Sᵢ into the digital signal D.[2]
- (b)(ii)The ADC and the DAC operate with the same sampling rate and the same number of bits in each digital number. State the effect on the transmitted analogue signal Sₜ when, for the ADC and the DAC, 1. the sampling rate is increased, 2. the number of bits in each digital number is increased. [2][2]
This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.
Mark scheme
Marking points from the official mark scheme (May/June 2017). The mark or mark type is shown in brackets.
- [B2] any two reasonable suggestions e.g. ∞ signal can be regenerated/noise removed (not "no noise") ∞ circuits more reliable ∞ circuits cheaper to produce ∞ multiplexing (is possible) ∞ error correction/checking ∞ easier encryption/better security
- [M1] samples the analogue signal
- [A1] at regular intervals and converts it (to a digital number)
- [B1] 1. smaller step depth
- [B1] 2. smaller step height
Write your answer and get it marked
On Oracle Prep you can write or photograph your own answer and have it marked by AI against this mark scheme, with feedback on what you missed.
Sign up free →