DP Physics (last assessment 2024)
Question 18M.2.HL.TZ1.7d
| Date | May 2018 | Marks available | [Maximum mark: 3] | Reference code | 18M.2.HL.TZ1.7d |
| Level | HL | Paper | 2 | Time zone | TZ1 |
| Command term | Determine | Question number | d | Adapted from | N/A |
d.
[Maximum mark: 3]
18M.2.HL.TZ1.7d
A capacitor consists of two parallel square plates separated by a vacuum. The plates are 2.5 cm × 2.5 cm squares. The capacitance of the capacitor is 4.3 pF.
(d)
In a different circuit, a transformer is connected to an alternating current (ac) supply.
The transformer has 100 turns in the primary coil and 1200 turns in the secondary coil. The peak value of the voltage of the ac supply is 220 V. Determine the root mean square (rms) value of the output voltage.
[3]
Markscheme
ALTERNATIVE 1
εs = × 220
= 2640 «V»
Vrms = = 1870 «V»
ALTERNATIVE 2
(Primary) Vrms = = 156 «V»
(Secondary) Vrms =
Vrms = 1870 «V»
Allow ECF from MP1 and MP2.
Award [2] max for 12.96 V (reversing Np and Ns).
[3 marks]
