CBSE(NCERT) GRADE 10 SCIENCE 2022 COMPARTMENT SET4

What is a functional group? Write the formula of functional group (a) alcohol, and (b) ketone.

(a) What is a triad? Write the names of three elements of such a triad.

What is Nuelands' law of octaves? Write the names of its two limitations.

(a) What is DNA? DNA copies generated may be similar but not identical. Give reason to justify this statement.

(b) What is variation? Why is variation beneficial to the species but not necessary for an individual?

What happens when a spirogyra filament attains maturation?

What happens when Planaria is cut into any number of pieces?

What happens when (a) a spirogyra filament attains maturation? (b) Planaria is cut into any number of pieces?

(a) What is the meaning of the following statement?

(b) On the basis of above statement, how can you arrive at a conclusion that the mother is not responsible for the sex of a child? Explain in brief.

(a) State Ohm's law. A student drew the $V$-$I$ graph on the basis of his experimental observations. Why should this graph be a straight line passing through the origin?

(b) When a $6.0\,\text{V}$ battery is connected across a resistor there is a current of $30\,\text{mA}$ in the circuit. Find the value of the resistance of

Explain the food chain of three trophic levels with the help of an example.

Why do we say that the flow of energy in an ecosystem is unidirectional? Explain with the help of a food chain having three trophic levels.

What is ozone? Which essential function does ozone perform at this level? In the 1980s, when it was found that the amount of ozone in the atmosphere was decreasing rapidly, what measures were taken?

How is ozone formed at the higher levels of the atmosphere? State how ozone performs the essential function at this level. In the 1980s when it was noticed that the amount of ozone in the atmosphere is dropping sharply, what steps were taken to save the atmosphere?

What is Biological magnification? How does it affect organisms present at various trophic levels, particularly the tertiary consumers?

What are structural isomers? Draw the structure of two isomers of butane $\mathrm{C_4H_{10}}$. Explain with the help of structure why we cannot have isomers of propane.

What is a homologous series of carbon compounds? Write the general formula of (i) alcohols, and (ii) aldehydes. Draw the structure of the first member of each series.

The atomic number of Calcium is 20. Answer the following questions stating the reason for each: (a) Is Calcium a metal or a non-metal? (b) Is the atomic radii of calcium larger or smaller than (i) potassium (atomic number 19), and (ii) iron (atomic number 26)? (c) Write the formula of its oxide.

In one of his experiments with pea plants, Mendel observed that when tall pea plants (TT) were crossed with dwarf pea plants (tt), in the first generation ($F_1$) plants only tall plants appeared. (a) What happens to the traits for dwarfness in this case? (b) When the $F_1$ generation plants were self-pollinated, he observed that in the plants of $F_2$ generation both tall plants and dwarf plants were present. Explain briefly why it happened. (c) Mention the ratio obtained in such a cross.

For a heater rated $4.4\ \mathrm{kW}$; $220\ \mathrm{V}$, calculate the following: (a) The current (b) The resistance of the heater (c) The energy consumed in kWh in 5 hours

(a) (i) What is a magnetic needle ? Why does a magnetic needle get deflected when brought near a current carrying straight conductor ? (ii) State right hand thumb rule. OR (b) (i) The magnetic field in a region is represented by equidistant parallel lines. What do such lines indicate ? (ii) Imagine that you are sitting in an examination room with your back to one wall. An electron beam moving horizontally from the back wall towards the front wall is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field ? (iii) State the rule which you have applied in determining the direction of the magnetic field in this case.

We are all aware of the term reproduction and we know that the continuity of life on our Earth from the origin to the present day has been possible only because of reproduction. Sexual reproduction is the most common mode of reproduction in flowering plants (angiosperms). Seeds are produced as a result of sexual reproduction. New plants are produced from these seeds only. In angiosperms, flower is the reproductive part of a plant. Most flowers have both male and female reproductive organs in them. (a) Name the (i) male, and (ii) female part of a flowering plant. (b) What happens to the zygote after fertilisation ? (c) (i) Differentiate between self-pollination and cross-pollination. OR (ii) Explain in brief, how fertilisation takes place in angiosperms.

A student wants to demonstrate a phenomenon of science in a science fair. He takes a straight solenoid fixed vertically on a wooden board and connects its two ends to a galvanometer. He also takes a strong bar magnet

A student wants to demonstrate a phenomenon of science in a science fair. He takes a straight solenoid fixed vertically on a wooden board and connects its two ends to a galvanometer. He also takes a strong bar magnet whose south pole is attached to a spring and suspends it with its axis vertical using a wooden stand in such a way that the north pole of the magnet is slightly above the upper end of the solenoid. He also ensures the free in and out movement of the north pole in the stationary solenoid. Now he pushes the magnet slightly downward and then releases it. The magnet starts oscillating. Based on your understanding, answer the following questions: (a) What is observed in the galvanometer when the magnet oscillates and why ? (b) What is observed in the galvanometer when the amplitude of oscillation is decreased to about one-half and why ? (c) (i) State the type of movement shown by the needle of the galvanometer. What may be the reason for such a motion ? Write the conclusion which can be drawn from this activity. OR (ii) Name and define the phenomenon demonstrated through this activity. Name the scientist who discovered this phenomenon.

What is observed in the galvanometer when the magnet oscillates and why ?

What is observed in the galvanometer when the amplitude of oscillation is decreased to about one-half and why ?

State the type of movement shown by the needle of the galvanometer. What may be the reason for such a motion ? Write the conclusion which can be drawn from this activity.

Name and define the phenomenon demonstrated through this activity. Name the scientist who discovered this phenomenon.