alleryStart learning →Current can be measured without breaking the circuit by detecting its:
AColour shade
BMagnetic field
CTotal mass
DSound level
Answer & Solution
Correct answer: B. Magnetic field
A current makes a magnetic field, and sensors can read that field from outside the wire.
Keep practising Electric current and its effects
Browse all Electric current and its effects questions for Olympiad (Class 7), or explore more Science topics.
Related questions
Which of these is used as a transformer insulator?The electric power delivered to homes is mostly:Aluminium is preferred for long power lines mainly because it is:Aluminium wire joints can heat up because aluminium readily forms an insulating:A flow of positive charge to the right has the same effect as an equal flow of negative chIn a metal wire, the positively charged atomic nuclei are:In metallic solids, electric charge flows by means of:For a fixed resistor, if the voltage across it rises, the current: