Class 7 Science Chapter 10 Electric Current And Its Effects Quiz 39 (8 MCQs)

Quiz Instructions

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1. In a Wheatstone bridge if the battery and galvanometer are interchanged then the deflection in galvanometer will
2. Iron used in bridges and automobiles are coated with
3. If we keep a compass inside a cardboard with cell and switch attached, it shows magnetic effect of current.
4. How can corrosion be prevented in iron?
5. Select the one that you will prefer to make an electromagnet.
6. A 10 cm long wire with a cross-sectional area of 5 mm$^{3}$ has a resistance of 40 $\Omega$. It is then replaced with a wire of the same material, 20 cm long and with a cross-sectional area of 20 mm$^{3}$. What is the new resistance?
7. The process of electromagnetic Induction was first discovered by:
8. When an electric current pass through by the conductors, the conductor .....