Electric Current and its Effects Sample Questions for Class 7
Question 1
Which of the following elements can form closed electric circuit?
A. Battery, bulb , switch
B. Switch, conducting wire, bulb
C. Battery ,conducting wire , bulb
D. Switch,conducting wire , bulb
Question 2
Which device works on magnetic effect of electric current?
A. Electric fan
B. Electric bulb
C. Electric bell
D. Electric mixer
Question 3
Heating effect of electric current is used in ?
A. Electric motor
B. Electric fuse
C. Electric bell
D. Electromagnet
Question 4
What can be added in pure water so that it can conduct electricity ?
A. Lime juice
B. Sodium chloride
C. Copper sulphate
D. All of the above
Question 5
HCL acid is added to water. Then current is passed through it , so in this process of electrolysis which gas will be collected at anode?
A. Chlorine
B. Hydrogen
C. Oxygen
D. A and C