Question 1 :
An earthquake measures 3 on Richter scale. Would it be recorded by a seismograph?
Question 2 :
State TRUE or FALSE : Lightning conductor cannot protect a building from lightning.
Question 3 :
State in India where earthquakes are more likely to strike is:
Question 4 :
The scale on which the destructive energy of an earthquake is measured is:
Question 5 :
State TRUE or FALSE : A charged glass rod attracts a charged plastic straw.
Question 6 :
State TRUE or FALSE : Earthquakes can be predicted in advance.
Question 8 :
The weather department has predicted that a thunderstorm is likely to occur an a certain day. Suppose you have to go out on that day. Would you carry an umbrella?
Question 10 :
Suppose you are outside your home and an earthquake strikes. Which of the following you should not do to protect yourself?
Question 11 :
When a glass rod is rubbed with a piece of silk cloth, the rod :
Question 12 :
An earthquake measures 3 on Richter scale. Is it likely to cause much damage?
Question 15 :
A pendulum oscillates 40 times in 4 seconds. Find its time period.
Question 18 :
State True or False: For human ears, the audible range is 20 Hz to 20,000 Hz
Question 19 :
State True or False: If the amplitude of vibration is large, sound is feeble.
Question 21 :
Fill in the blank: Shrillness of a sound is determined by the _____ of vibration.
Question 22 :
We have a stringed musical instrument. The string is plucked in the middle first with a force of greater magnitude and then with a force of smaller magnitude. In which case would the instrument produce a louder sound?
Question 25 :
Boojho saw a cracker burst at night at a distance from his house. He heard the sound of the cracker a little later after seeing the cracker burst. Give reason for the delay in hearing the sound.
Question 27 :
Your parents are going to buy a house. They have been offered one on the roadside and another three lanes away from the roadside. Which house would you suggest your parents should buy?
Question 28 :
Unwanted or unpleasant sound is termed as music. True or False ?
Question 30 :
Noise pollution may cause partial hearing impairment. Is that correct ?
Question 31 :
How can we recognize many familiar sounds without seeing the objects producing them?
Question 32 :
A pendulum oscillates 40 times in 4 seconds. Find its frequency.
Question 33 :
Fill in the blank: Time taken by an object to complete one oscillation is called ______.
Question 35 :
Presence of excessive noise in the surroundings may cause many health related problems. True or false ?
Question 36 :
If the amplitude of vibration is large, sound is feeble. State true or false.
Question 39 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d05ef59b460d7261f2d9.PNG' />
In the image above, will the bulb glow. Write ‘Yes’ or ‘No’
Question 40 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d05ff59b460d7261f2da.PNG' />
In the image above, will the bulb glow. Write ‘Yes’ or ‘No’
Question 41 :
One of the most common applications of chemical effect of electric current is __________.
Question 42 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d058f59b460d7261f2d1.PNG' />
Current does not flow in the circuit if there is a gap between the two wires. Does it indicate that air is a poor conductor of electricity?
Question 43 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d05cf59b460d7261f2d7.PNG' />
In the image above, will the bulb glow. Write ‘Yes’ or ‘No’
Question 44 :
One of the most common applications of chemical effect of electric current is __________.
Question 45 :
A coating of zinc is provided to protect iron from corrosion and rust.
Question 46 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d050f59b460d7261f2c7.PNG' />
Current does not flow in the circuit if there is a gap between the two wires. Does air never conduct electricity?
Question 48 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d056f59b460d7261f2cf.PNG' />
In the image above, Boojho set up this circuit for purification of copper. What will be the nature of plate A?
Question 49 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d059f59b460d7261f2d3.PNG' />
From the above image, we can see that Boojho and Paheli performed experiments taking similar bulbs and cells but two different solutions A and B. They found that the bulb in the setup A glows more brightly as compared to that of the setup B. You would conclude that
Question 51 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
Question 52 :
Boojho’s uncle has set up an electroplating factory near his village. He should dispose off the waste of the factory
Question 53 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d050f59b460d7261f2c8.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. Why did the bulb not glow in A?
Question 54 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d051f59b460d7261f2c9.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. What will be observed if the number of cells are increased in the circuit shown in B?
Question 55 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d058f59b460d7261f2d2.PNG' />
In the above image, which of the following solutions will not make the bulb glow?
Question 56 :
Which of the following metals is used in electroplating to make objects appear shining?
Question 57 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d059f59b460d7261f2d3.PNG' />
From the above image, we can see that Boojho and Paheli performed experiments taking similar bulbs and cells but two different solutions A and B. They found that the bulb in the setup A glows more brightly as compared to that of the setup B. You would conclude that
Question 58 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d054f59b460d7261f2cd.PNG' />
In the image above, Boojho set up this circuit for purification of copper. What will be the nature of plate B?
Question 59 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d051f59b460d7261f2c9.PNG' />
In the above image, observing that the bulb does not glow in the circuit shown in A, Boojho changed the circuit as shown in B. He observed deflection in the magnetic compass. What will be observed if the number of cells are increased in the circuit shown in B?
Question 60 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
