Which of the following statements is correct?
(a) All metals are ductile.
(b) All non-metals are ductile.
(c) Generally, metals are ductile.
(d) Some non-metals are ductile.
(c) Generally, metals are ductile
Generally metals are ductile but some exceptions are there like mercury is a metal which is liquid at room temperature. It cannot be drawn into wires, so it is not ductile.
Describe with the help of a diagram an instrument which can be used to detect a charged body.
Sketch larynx and explain its function in your own words.
Arrange the following boxes in proper order to make a flow chart of sugarcane crop production.
Make a labelled diagram of a candle flame.
What is metamorphosis? Give examples.
The following Table shows the total power shortage in India from 1991– 1997. Show the data in the form of a graph. Plot shortage percentage for the years on the Y-axis and the year on the X-axis.
Make sketches of animal and plant cells. State three differences between them.
What is a constellation? Name any two constellations.
Describe the construction of a kaleidoscope.
Complete the crossword with the help of clues given below:
Across
1. This is necessary for photosynthesis.
3. Term for component present in the cytoplasm.
6. The living substance in the cell.
8. Units of inheritance present on the chromosomes.
Down
1. Green plastids.
2. Formed by collection of tissues.
4. It separates the contents of the cell from the surrounding medium.
5. Empty structure in the cytoplasm.
7. A group of cells.
Describe the process of fertilization in human beings.
What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray?
Why is the distance between stars expressed in light years? What do you understand by the statement that a star is eight light years away from the Earth?
Write 10 lines on the usefulness of microorganisms in our lives.
The bulb does not glow in the setup shown in Fig.14.10. List the possible reasons. Explain your answer.
Name the petroleum product used for surfacing of roads.
When we press the bulb of a dropper with its nozzle kept in water, air in the dropper is seen to escape in the form of bubbles. Once we release the pressure on the bulb, water gets filled in the dropper. The rise of water in the dropper is due to
(a) pressure of water
(b) gravity of the earth
(c) shape of rubber bulb
(d) atmospheric pressure
Describe the ‘Green House Effect’ in your own words.
Match items in column A with one or more items in column B:
A B
(i) Inner planets (a) Saturn
(ii) Outer planets (b) Pole Star
(iii) Constellation (c) Great Bear
(iv) Satellite of the Earth (d) Moon
(e) Earth
(f) Orion
(g) Mars
Fill in the blanks with suitable words.
(a) Time taken by an object to complete one oscillation is called ................... .
(b) Loudness is determined by the .........................of vibration.
(c) The unit of frequency is..........................
(d) Unwanted sound is called ......................... .
(e) Shrillness of a sound is determined by the ................. of vibration.