List of top Questions asked in CBSE Class X

Find the magnification of the image formed by a spherical mirror from the following data :
$u = -20$ cm,  $f = -15$ cm.

“In human beings, the sex of a newborn child depends on the father and not the mother.” Justify this statement with the help of a flow diagram.
Name the glands which add their secretions to the sperms. List two functions of these secretions.
Are these compounds soluble in organic solvents such as kerosene or petrol? Justify your answer.
When two compounds namely sodium chloride and calcium chloride are heated directly, one by one on the flame of a burner, they impart different colours to the flame.
Name the colour imparted by (1) sodium chloride and (2) calcium chloride.
Assertion (A) : A rainbow is an artificial spectrum of white light appearing in the sky after a rain shower.
Reason (R) : The water droplets act like small prisms.
Assertion (A) : Each human trait is influenced by both paternal and maternal DNA.
Reason (R) : As compared to the father, the mother contributes more amount of genetic material to the child.
Assertion (A) : A hormone called abscisic acid inhibits growth in plants.
Reason (R) : The role of auxins is opposite to that of abscisic acid in plants.
The shape of magnetic field lines produced (i) inside a solenoid (ii) around a straight conductor, both carrying current of the same magnitude are, respectively :

The resistance of a wire does not depend on its :

A material used for making heating elements of electrical heating devices should have :
The organism in which an outgrowth on the parent body develops into a new individual is :
Which one of the following metals is malleable and a poor conductor of electricity ?
In the electrolysis of water, if the mass of the gas collected at the anode is $m_a$ and the mass of the gas collected at the cathode is $m_c$, the value of $\frac{m_c}{m_a}$ is :
Express each number as a product of its prime factors: 
  1. \(140\) 
  2. \(156\) 
  3. \(3825\) 
  4. \(5005\) 
  5. \(7429\)
Write the balanced chemical equations for the following reactions. 
(a) Calcium hydroxide + Carbon dioxide \(→\) Calcium carbonate + Water 
(b) Zinc + Silver nitrate \(→\) Zinc nitrate + Silver 
(c) Aluminium + Copper chloride \(→\) Aluminium chloride + Copper 
(d) Barium chloride + Potassium sulphate \(→\) Barium sulphate + Potassium chloride
What does Kisa Gotami understand the second time that she failed to understand the first time? Was this what the Buddha wanted her to understand?
Do you think books are being replaced by the electronic media? Can we do away with books altogether?
Horace Danby was a meticulous planner but still he faltered. Where did he go wrong and why?
“Horace Danby was good and respectable — but not completely honest”. Why do you think this description is apt for Horace? Why can’t he be categorised as a typical thief?
Find the sums given below :
  1. \(7 + 10\frac 12+ 14 + ....... + 84\)
  2. \(34 + 32 + 30 + ....... + 10\)
  3. \(–5 + (–8) + (–11) + ....... + (–230)\)
Do you think people like Anil and Hari Singh are found only in fiction, or are there such people in real life?
Prove that \(3 + 2\sqrt 5\) is irrational.
Solve the following pair of linear equations by the elimination method and the substitution method : 
(i) x + y = 5 and 2x – 3y = 4
(ii) 3x + 4y = 10 and 2x – 2y = 2 
(iii) 3x – 5y – 4 = 0 and 9x = 2y + 7 
(iv)\( \frac{x}{2} + \frac{2y}{3} = -1 \) and \(x- \frac{y}{3} = 3\)
Why does Anne need to give a brief sketch about her family? Does she treat ‘Kitty’ as an insider or an outsider?