List of top Questions asked in CBSE Class VIII

1.  \(4p^ 2 - 9q ^2\) 
2.  \(63a^ 2 - 112b ^2\) 
3.  \(49x^ 2 - 36\) 
4.  \(16x^ 5 - 144x^ 3\)
5.  \((l + m)^ 2 - (l - m) ^2\) 
6.  \(9x^ 2 y^ 2 - 16 \)
7.  \((x^ 2 - 2xy + y^ 2 ) - z^ 2\) 
8.  \(25a ^2 - 4b^ 2 + 28bc - 49c ^2\)

1. (a) a prime number (b) not a prime number. 
2. (a) a number greater than 5 (b) a number not greater than 5.

1. Sound cannot travel in vacuum. (T/F)
2. The number of oscillations per second of a vibrating object is called its time period. (T/F)
3. If the amplitude of vibration is large, sound is feeble. (T/F)
4. For human ears, the audible range is 20 Hz to 20,000 Hz. (T/F)
5. The lower the frequency of vibration, the higher is the pitch. (T/F)
6. Unwanted or unpleasant sound is termed as music. (T/F)
7. Noise pollution may cause partial hearing impairment. (T/F)

1.  \(a^ 2 + 8a + 16 \)
2. \(p^ 2 - 10p + 25 \)
3. \(25m^2 + 30m + 9 \)
4. \(49y^ 2 + 84yz + 36z ^2 \)
5. \(4x^ 2 - 8x + 4 \)
6. \(121b ^2 - 88bc + 16c ^2 \)
7. \((l + m) ^2 - 4lm \) (Hint: Expand \((l + m) ^2 \) first)
8.  \(a^ 4 + 2a ^2b ^2 + b^ 4\)

1. a quadrilateral 
2. a parallelogram 
3. a rhombus 
4. a rectangle

Which words in the list below describe Sanjeev, in your opinion? (Look up the dictionary for words that you are not sure of.) 

Use words from the list to complete the three sentences below. 

(i) I don’t know if Sanjeev was cheerful, _____ or _____. 

(ii) I think that he was very brave,____ and_____. 

(iii) Sanjeev was not heartless, _____or_____.