Question 1 :
One of the most common applications of chemical effect of electric current is __________.
Question 2 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
Question 5 : <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 6 : <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 7 :
When electric current is passed through a conducting solution, there is a change of colour of the solution. This indicates
Question 9 : <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 10 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d05cf59b460d7261f2d6.PNG' />
In the image above, will the bulb glow. Write ‘Yes’ or ‘No’
Question 11 : <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 12 :
One of the most common applications of chemical effect of electric current is __________.
Question 13 : <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 14 :
Heating effect of electric current is the effect of current responsible for the glow of the bulb in an electric circuit.
Question 15 : <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 16 : <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 17 : <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 18 : <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 19 : <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 20 :
Boojho’s uncle has set up an electroplating factory near his village. He should dispose off the waste of the factory
Question 21 :
What precautions should be taken if you are outside the house during a earthquake?
Question 24 :
Electrical charge can be transferred from a charged object to another through a
Question 26 :
The earthquake measuring ______ or more on Richter scale can cause severe damage to life and property.
Question 27 :
If the materials used for constructing a building were good conductors, do you think lightning will strike the building?
Question 28 :
An earthquake measures 3 on the richer scale. Would it be recorded by a seismograph?
Question 29 :
It is a convention to call the charge acquired by a glass rod when it is rubbed with silk as ___________.
Question 31 :
The power of an earthquake is expressed in terms of a magnitude on a scale called
Question 33 :
In an electroscope if a negatively charged body is brought in contact with the metal clip, the strips of the electroscope diverge. If now another charged object carrying equal amount of positive charge is brought in contact with the clip, what will happen?
Question 34 :
What precautions should be taken if you are Inside the house during a thunderstorm?
Question 35 :
The outermost layer of the earth is not in one piece. It is fragmented. Each fragment is called :
Question 40 :
Which states in India where earthquakes are more likely to strike?
Question 41 : <img style='object-fit:contain' src='https://teachmint.storage.googleapis.com/question_assets/cbse_ncert/61b1d0abf59b460d7261f333.jpeg' />
In the above figure an alarm bell is kept inside a vessel. A person standing close to it can distinctly hear the sound of alarm. Now if the air inside the vessel is removed completely how will the loudness of alarm get affected for the same person?
Question 42 :
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 43 :
Time taken by an object to complete one oscillation is called __________.
Question 45 :
The sound from a mosquito is produced when it vibrates its wings at an average rate of 500 vibrations per second. What is the time period of the vibration?
Question 46 :
State True or False: If the amplitude of vibration is large, sound is feeble.
Question 49 :
Fill in the blank: Time taken by an object to complete one oscillation is called ______.
Question 50 :
In order to reduce the loudness of a sound we have to
Question 51 :
State true or false. A whistle has a high frequency and therefore, produces a sound of low pitch
Question 53 :
State True or False: The lower the frequency of vibration, the higher is the pitch.
Question 54 :
State True or False: Noise pollution may cause partial hearing impairment.
Question 57 :
Loudness of sound is proportional to the square of the amplitude of the vibration producing the sound. State true or false.
