Class 10 previous year questions (PYQ)

Write 'True' or 'False' and give reasons for your answer.
In the figure,$BOA$ is a diameter of a circle and the tangent at a point $P$ meets $BA$ extended at $T$. If $\angle PBO = 30^{\circ}$,then $\angle PTA$ is equal to $30^{\circ}$.

Directions: In the question below, a statement of Assertion (A) is followed by a statement of Reason (R). Choose the correct option:

Assertion (A): Money serves as an indispensable medium of exchange in modern market economies.

Reason (R): Money eliminates the need for double coincidence of wants inherent in barter trade systems.

What are the qualities of an ideal source of energy?

Find the area of the shaded region in the figure if $PQ = 24 \, cm$,$PR = 7 \, cm$ and $O$ is the centre of the circle. [Use $\pi = \frac{22}{7}$]

The cost of fencing a circular field at the rate of $Rs. 24$ per metre is $Rs. 5280$. The field is to be ploughed at the rate of $Rs. 0.50$ per $m^2$. Find the cost of ploughing the field (Take $\pi = \frac{22}{7}$). (in $Rs.$)

$A$ substance $X$, which is an oxide of a group $2$ element, is used intensively in the cement industry. This element is present in bones also. On treatment with water, it forms a solution which turns red litmus blue. Identify $X$ and write the chemical reactions involved.

How many tangents can a circle have?

According to the CBSE curriculum for Class 10, which analytical factor is paramount when evaluating 'Nationalism in India (First World War, Khilafat and Non-Cooperation, Differing Strands within Movement, Towards Civil Disobedience, The Sense of Collective Belonging)' in 'India and the Contemporary World II (History)'?

$A$ bag contains orange flavoured candies only. Rahi takes out one candy without looking into the bag. Then,the probabilities that the candy taken out is orange flavoured and is lemon flavoured are ........ respectively.

$A$ box contains $5$ red,$8$ white,and $4$ green balls. If a ball is drawn at random from the box,find the probability that the ball drawn is red.

Which of the following oxide$(s)$ of iron would be obtained on prolonged reaction of iron with steam?

The smell and taste of food containing fats and oils change after some time. Why does this happen? Name the process. List two ways which help to slow down the above-mentioned process.

$(a)$ Distinguish between homologous and analogous organs.
$(b)$ State one evidence of organic evolution.

The figure below shows the refraction and emergence of a ray of light incident on a rectangular glass slab. Copy the diagram and mark the lateral displacement of the incident ray. Name the two factors on which the lateral displacement depends.

Oil and fat containing food items are flushed with nitrogen. Why?

Which among the following statement$(s)$ is(are) true? Exposure of silver chloride to sunlight for a long duration turns grey due to
$(i)$ the formation of silver by decomposition of silver chloride
$(ii)$ sublimation of silver chloride
$(iii)$ decomposition of chlorine gas from silver chloride
$(iv)$ oxidation of silver chloride

While diluting an acid,why is it recommended that the acid should be added to water and not water to the acid?

Which of the following is(are) true when $HCl(g)$ is passed through water?
$(i)$ It does not ionise in the solution as it is a covalent compound.
$(ii)$ It ionises in the solution.
$(iii)$ It gives both hydrogen and hydroxyl ion in the solution.
$(iv)$ It forms hydronium ion in the solution due to the combination of hydrogen ion with water molecule.

Which type of an image is formed by a plane mirror?

"Experiences of an individual during its lifetime cannot be passed on to its progeny and cannot direct evolution". Justify this statement giving an example.

Which substance is used for the chemical reduction of metal oxides like chromium and manganese to obtain the metal?

Identify the functional groups present in the following compounds:
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If $1$ mole of glucose is dissolved in $500 \; mL$ of glucose solution,what is the molarity of the solution (in $; M$)?

To protect against tooth decay,we are advised to brush our teeth regularly. The nature of the toothpaste commonly used is: