The National Grid is used to transfer electrical energy from power stations to consumers - AQA - A-Level Physics - Question 24 - 2017 - Paper 2
Question 24
The National Grid is used to transfer electrical energy from power stations to consumers.
What conditions for the transmission voltage and the transmission current ... show full transcript
Worked Solution & Example Answer:The National Grid is used to transfer electrical energy from power stations to consumers - AQA - A-Level Physics - Question 24 - 2017 - Paper 2
Step 1
Transmission voltage: High
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Using a high transmission voltage reduces the current for a given power transfer. This minimizes energy losses due to resistance in the cables, thus making the transfer more efficient.
Step 2
Transmission current: Low
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Maintaining a low transmission current alongside high voltage results in lower I²R losses (where I is the current and R is the resistance). Therefore, this combination is optimal for efficient energy transfer.
