Ncert – class 8- science – Chapter 12: Some Natural Phenomena 1 Welcome to your Ncert - class 8- science - Chapter 12: Some Natural Phenomena 1 1. What are the weak zones around the boundaries of plates underneath Earth, which are prone to slide and cause earthquakes? Fault zone Explosive zone Sliding zone Eruption zone 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? (i) (iv) (iii) (ii) None 3. What is a positive charge? The charge acquired by a glass rod when it is rubbed with silk The charge acquired by plastic straw when it is rubbed with a silk None of these The charge acquired by silk when it is rubbed with a glass rod None 4. Lightning is caused in the atmosphere primarily due to None of these Opposite charges accumulation at edges of a cloud. Discharge between one charged and one neutral cloud. Discharge between two similarly charged clouds. None 5. If the Richter scale reading for an earthquake is less than 3.5 then what can you say about the earthquake? Often felt & rarely causes damage Generally not felt but recorded Major earth quake causes serious damage Causes major damage to poorly constructed buildigs None 6. Two objects when rubbed together, get charged. The charges on them are: Unequal and similar Equal and similar Unequal and opposite Equal and opposite None 7. 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 not diverge the plastic strips will diverge the plastic strips will come more closer. None 8. The process of transferring a charge from a charged body to the earth is called Electrolysis Discharging Earthing Hydrolysis None 9. Why is Earthing done in buildings? None of these To protect us from electric shocks To give extra strength to the building To transfer extra current to air None 10. An ebonite rod is rubbed with fur. The charge on the ebonite rod is ______ and the charge on the fur is _______. Negative, Negative Negative, Positive Positive, Positive Positive, Negative None 11. What happens when two bodies are rubbed together They get equal charged but the opposite nature They get equal charged but the same nature None Nothing happend with rubbing None 12. During the thunderstorm, ________ move upwards while ________ move downards. Water droplets, air currents Air currents, charges Water droplets, charges Air currents, water droplets None 13. Like charges repel and unlike charge Attract each other Any thing may happen Repel each other Repel or attract None 14. 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 negative charges Meeting of unlike electric charges None 15. Which of the following is not a natural phenomenon? Earthquake Cooking Cyclone Lightening None 16. Which of the following natural phenomenon is most destructive in terms of loss of life and property? Storms Lightening Earthquake winds None 17. Some object can be charged by _________ with other objects. Heating Rubbing Touching Joining None 18. 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 19. How does charges separate during a thunderstorm? Due to movement of air None of these Due to rubbing of air particles Due to movement of air current and water droplets None 20. Building can be protected from lightening by using All of these Lightening rod at the top of building Wooden logs at the top of building Lightening rod on the levels of building 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.
