V = IR and P = VI
Practice Flashcards
Flip to reveal answersState both equations and their rearrangements.
Track your progress — Sign up free to save your progress and get smart review reminders based on spaced repetition.
All 4 Flashcards — V = IR and P = VI
Sign up free to track progress and get spaced-repetition review schedules.
Question
State both equations and their rearrangements.
Answer
V = I × R, so I = V ÷ R and R = V ÷ I. P = V × I, so V = P ÷ I and I = P ÷ V.
Question
What single step prevents most calculation errors?
Answer
Converting to base units before substituting — milliamps into amps, kilohms into ohms.
Question
How is battery life calculated?
Answer
Total charge used per day in mAh, then divide the cell rating by it. A 2,000 mAh cell supplies 20 mA for 100 hours.
Question
Why calculate the power in a resistor?
Answer
It decides the physical size of the part. A quarter-watt resistor dissipating half a watt runs hot, drifts in value and eventually fails.
Read the notes
Full study notes for V = IR and P = VI
Topic 7.4 hub
Electronic systems applied
More from Topic 7.4
All flashcards in this topic
Design Technology exam skills
Paper structures & tips
Track your progress with spaced repetition
Sign up free — Aimnova tells you exactly which cards to review and when, so you remember everything before your IB exam.
Start Free