CBSE Class 7 Science Science And Technology Worksheet

1. Explain the formation of cyclones.

2. Write four precautions to be followed in case of a thunderstorm.

3. Differentiate between uniform speed and non-uniform speed. Explain the term average speed.

4. On a 120 km track, a train travels 30 km at a uniform speed of 30 km/h. How fast must the train travel the next 90 km so as to average 60 km/h for entire trip?

5. Can a body be at rest as well as in motion at same time? Explain.

6. Explain following terms –

(i) Amplitude

(ii) Time-period

7. A girl took five complete revolutions on a giant wheel, having 7m diameter. Calculate distance traveled by her in cm.

8. Draw the distance-time graph when

(i) The object is at rest.

(ii) The object is in uniform motion.

(iii) The object is in non-uniform motion.

Section – B : Chemistry

1. Match the following.

i) Element a) combination of elements in fixed ratio

ii) Compound b) pure substance having only one type of atoms

iii) Ions c) Combination without any reaction

iv) Mixture d) charged species

2. Write the name of the following symbol.

He , Fe, Cl, Be, C , Zn H, Ag, Au, Cu.

3. Indicate whether the following is physical or a chemical change.

a) Evaporation of water

b) Neutralization reaction

c) Sublimation of camphor

d) Milk turns into curd

e) Rusting of Iron

f) Hydrous salt change into anhydrous salt

g) Burning of paper

4. Define the following.

a) Galvanization b) Crystallization c) Rusting of Iron

5. Balance the following chemical equations.

i) NaOH + H₂SO₄ == ______ + H₂O

ii) Ca(OH)₂ + CH₃COOH ==== _______ + _______

Section – C : Biology

1. ‘Animals living in the forest help it to grow and regenerate’. Justify this statement by giving examples.

2. Draw the labelled diagram of the soil profile.

3. What is seed dispersal? What is the importance of seed dispersal? Mention the various agents of seed dispersal giving an example for each.

4. Mention the importance of forests.

5. Write three differences between sandy and clayey soil.

6. What is fertilization? With the help of labelled diagram, show the process of fertilization in plants.

7. What are decomposers? What is the significance of decomposers in forest?

8. Explain the mode of reproduction in yeast with the help of a diagram.

Section – A : Physics

1) What is fuse wires generally made off? Why is it used?

2) Describe the working of an electric-bell with the help of diagram.

3) Difference between :

a) convex and concave mirror.

b) regular and irregular reflection.

4) Find the position, nature and size of the image when an object is placed at C, F and between

C and F in front of cocave mirror.

5) Write the properties of image formed by a plane mirror.

6) When a narrow beam of sunlight is made to fall on a triangular glass prism, and a white screen is held on the other side of the prism, we observe a band of seven colour on the screen. The colour sequence obtained on the screen from its lower end s given by famous acronym VIBGYOR.

a) Define this phenomenon.

b) Give any one example of dispersion of sunlight in nature.

c) What value of life do you learn from this phenomenon?

Section – B : Chemistry

1. Differentiate between :

a) an acid and a base

b) Strong acid and weak acid

c) Hydrated and anhydrous salt

2. What are indicators? Name any two acid base indicators.

3. Define neutralization reaction .Give an example.

4. Give reason :

a) Why do we apply calamine lotion on the skin at the bee sting site?

b) Soil of an agricultural field has become too basic, how will you correct it.

5. What is meant by depletion of water table?

6. Define the term :

a) infiltration b) aquifer c) water table d) drip irrigation

7. Value Based Question:

Due to the disposal of the different kinds of waste in the water bodies, water gets polluted.

Suggest some measures for the proper disposal of the waste. What moral values are associated with the above statement.

Section – C : Biology

1. What is meant by absorption, assimilation and digestion ?

2. What are villi?

3. Draw a well labelled diagram of digestive system found in ruminants.

4. How does exchange of gases take place in plants, earthworm and fishes?

5. Distinguish between arteries and veins.

6. How transport of water and minerals take place in plants?

7. List two causes and consequences of deforestation?

8. What are decomposers?

9. A teacher assigned his students a task to find out blood group of any ten of their friends or family members and make a chart of blood group that each one can receive from in case of emergency.

a. What might be the objective of this activity?

b. What values does the objective signify?