CBSE Class 8 Science Electricity Magnetic and Heating Effects (Class 8 NCERT New) Quiz 8

1. Who discovered heating effect of elecric current?

A James Watt B Joule-Lenz C Michael Faraday D Thomas Edison

2. Tick the electric apps working with mechanical effect of electric current

A Juice squeezer B Electric oven C Compass D Electric kettle

3. When an electric current pass through by the conductors, the conductor ___________ ______

A to begin crash B going to freeze C heats up D going to melt

4. One advantage for physiological effects of electric current

A Respiratory paralysys B Organ start to burn C Tissue start to burn D Galvanotherapy

5. One disadvantage for physiological effects of electric current

A Respiratory paralysys B Electro Shocker – for the safety C To do echo-cardiogram D Galvanotherapy

6. What kind of process don't go when observe the chemical effect of electric current

A Formation of gas bubbles at the electrodes B Deposit of metal on the electrodes C Electric motor begin to move D Change in colour of the solution

7. How does electric current create a magnetic field?

A Electric current creates a magnetic field by heating the conductor. B Electric current generates a magnetic field only in superconductors. C Electric current produces a magnetic field through static electricity. D Electric current creates a magnetic field by the movement of charged particles, as described by Ampère's law.

8. What is the relationship between the strength of the current and the magnetic field?

A The strength of the current is directly proportional to the strength of the magnetic field. B The strength of the magnetic field is independent of the current. C The strength of the current has no effect on the magnetic field. D The strength of the current is inversely proportional to the strength of the magnetic field.

9. Name one factor that affects the strength of an electromagnet.

A Distance from the power source B Electric current C Magnetic field strength D Type of material

10. How does the number of coils in a wire affect the strength of an electromagnet?

A The number of coils has no effect on the strength of an electromagnet. B Increasing the number of coils in a wire increases the strength of an electromagnet. C More coils make the electromagnet weaker due to resistance. D Increasing the number of coils decreases the strength of an electromagnet.