Describe an activity to show that the incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.
The laws of reflection of light can be verified by the following activity:
Conclusion: This activity shows that the mirror incident ray, the reflection ray and the normal at the point of incidence, all lie on the same plane. The angle of the incidence is also equal to the angle of reflection. Thus, this activity verifies the laws of reflection.
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.
Fill in the blanks :
(a) Fossil fuels are , and .
(b) Process of separation of different constituents from petroleum is called .
(c) Least polluting fuel for vehicle is .
Describe the threat to the beauty of the Taj Mahal.
Write 10 lines on the usefulness of microorganisms in our lives.
Prepare a brief speech on global warming that you have to make in your class.
Write a short paragraph on the harms caused by microorganisms.
Explain why fossil fuels are exhaustible natural resources.
Tick True/False against the following statements :
(a) Fossil fuels can be made in the laboratory. (T/F)
(b) CNG is more polluting fuel than petrol. (T/F)
(c) Coke is almost pure form of carbon. (T/F)
(d) Coal tar is a mixture of various substances. (T/F)
(e) Kerosene is not a fossil fuel. (T/F)
Prepare a list of objects around you that are electroplated.
A blacksmith hammers a hot piece of iron while making a tool. How does the force due to hammering affect the piece of iron?
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.