Ncert – class 8- science – Chapter 12: Some Natural Phenomena 1 Welcome to your Ncert - class 8- science - Chapter 12: Some Natural Phenomena 1 1. An ebonite rod is rubbed with fur. The charge on the ebonite rod is ______ and the charge on the fur is _______. Negative, Positive Positive, Negative Negative, Negative Positive, Positive None 2. Following are precautions one must take in case a storm is accompanied by lightning. i) Do not take shelter under a tree. ii) Do not take shelter under an umbrella with a metallic end. iii) Do not take shelter in open garages, storage sheds, etc. iv) Do not take shelter in a bus in the open. Which one of these is not correct? (iii) (i) (iv) (ii) None 3. Which of the following is not a natural phenomenon? Earthquake Cyclone Lightening Cooking None 4. Why is Earthing done in buildings? To give extra strength to the building None of these To protect us from electric shocks To transfer extra current to air None 5. Building can be protected from lightening by using All of these Wooden logs at the top of building Lightening rod at the top of building Lightening rod on the levels of building None 6. Two objects when rubbed together, get charged. The charges on them are: Unequal and similar Unequal and opposite Equal and similar Equal and opposite None 7. What happens when two bodies are rubbed together Nothing happend with rubbing They get equal charged but the same nature They get equal charged but the opposite nature None None 8. When a glass rod is rubbed with dry silk cloth, the charge acquired by the silk cloth is Positive none of the above Negative Both positive and negative None 9. What are the weak zones around the boundaries of plates underneath Earth, which are prone to slide and cause earthquakes? Explosive zone Fault zone Eruption zone Sliding zone None 10. In an electroscope, if aluminium strips are replaced by plastic strips, and a charged object is touched with the metal top of the electroscope: one strip will move away while other will remain same. the plastic strips will come more closer. the plastic strips will diverge the plastic strips will not diverge None 11. The process of transferring a charge from a charged body to the earth is called Hydrolysis Electrolysis Earthing Discharging None 12. Lightning is caused in the atmosphere primarily due to Opposite charges accumulation at edges of a cloud. None of these Discharge between two similarly charged clouds. Discharge between one charged and one neutral cloud. None 13. Like charges repel and unlike charge Repel or attract Repel each other Attract each other Any thing may happen None 14. How does charges separate during a thunderstorm? Due to movement of air current and water droplets Due to rubbing of air particles None of these Due to movement of air None 15. If the Richter scale reading for an earthquake is less than 3.5 then what can you say about the earthquake? Generally not felt but recorded Causes major damage to poorly constructed buildigs Often felt & rarely causes damage Major earth quake causes serious damage None 16. During the thunderstorm, ________ move upwards while ________ move downards. Water droplets, charges Air currents, charges Water droplets, air currents Air currents, water droplets None 17. What is a positive charge? The charge acquired by plastic straw when it is rubbed with a silk The charge acquired by silk when it is rubbed with a glass rod None of these The charge acquired by a glass rod when it is rubbed with silk None 18. Which of the following natural phenomenon is most destructive in terms of loss of life and property? Lightening Earthquake Storms winds None 19. Some object can be charged by _________ with other objects. Rubbing Touching Heating Joining None 20. What is the cause for the streaks of bright light and sound produced during lightning? Meeting of positive charges Meeting of like electric charges Meeting of unlike electric charges Meeting of negative charges None Time's up Please Share This Share this content Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Opens in a new window Leave a Reply Cancel replyCommentEnter your name or username to commentEnter your email address to commentEnter your website URL (optional) Save my name, email, and website in this browser for the next time I comment.
