CBSE Sample Paper 2021 Class 7 Science Annual Examination

Annual Examination

Class-VII

Sub- Science

Time: 2:30 hour/M.M.-80

All questions are compulsory.

1- Tick the correct option.(5)

i) One solar day is equal to

a- 24 hour

b- 1440 min

c- 86400 sec

ii) The standard unit of speed is

a- Km/h

b- m/s

c- m/h

iii) Which of the following does not allow the electric current to pass through them?

a- Cell

b- rubber

c- brass

iv) The rear view and side view glasses in cars are made of

a- Concave mirror

b- concave lens

c- convex mirror

v) Tornadoes are also called

a- Hurricanes

b- twisters

c- typhoons

vi) The percentage of water present in human body

a- 50%

b- 60%

c- 70%

vii) Which of the following is not a forest product?

a- Gum

b- perfume

c- kerosene

viii) Which one is a carnivore?

a- Rabbit

b- lion

c-   cow

ix) Increased growth of algae occurs due to the presence of

a- Nitrates

b- phosphates

c- sulphates

x) Which one is a conductor of electricity?

a- Rubber

b- copper

c- wood

2- State true or false statement. (5)

i) Fuse wire has a low electric resistance.

ii) Fuse wire melts when the circuit is overloaded.

iii) Winds blow from land to ocean in winter.

iv) An increase in pressure indicates the possibility of a steam.

v) Decomposers are producers.

vi) Forest brings about global warming.

vii) Bacteria and fungi are decomposers.

viii) Rabbit is an herbivore animal.

ix) Dried sludge can be used as manure.

x) Stagnant water does not lead to any disease.

3- Fill in the blanks. (5)

i) Forests occupy about __________ of the world’s total land area.

ii) Seawater is __________in taste.

iii) Groundwater is obtained with the help of______ and_______.

iv) Moving air is called__________.

v) Air pressure __________when wind speed increases.

vi) An anemometer measures__________.

vii) The torch makes use of __________ for reflector.

viii) A fuse wire has __________ electric resistance.

ix) The time gap between two events is called __________.

4- Match correctly.(7)

i) One second                       saline water

ii) Fuse                                  a unit of time

iii) Green wire                     safety device

iv) Ocean water                  earth wire

v) Water                               table cholera

vi) Waste water                  upper level of groundwater

vii) Water borne disease       used water

5- Define the following.(8)

i) Mirror

ii) food chain

iii) Lens

iv) sewage

6- Differentiate between the following. (Do any 2)(4)

i) Thunderstorm and cyclones

ii) Real image and virtual image

iii) Convex lens and concave lens

7- Answer the following questions in brief.(any 8) (16)

i) Define oscillation and time period of a pendulum.

ii) What are the causes of fire in electric circuit?

iii) Why a concave lens is called a diverging lens?

iv) How is wind produced?

v) What are the three states of water?

vi) What are the different sources of water?

vii) List five products we get from forests?

viii) What are understoreysin a forests?

ix) How plants are dependent on animal?

8- Answer the following questions in detail.(Do any 5)(20)

i) What are conductors? How are they useful in an electric circuit?

ii) Why is sea and ocean water unfit for human consumption?

iii) In which all ways is water important to us?

iv) How can we conserve forests?

v) A bus takes 2 hours to cover a distance of 80km calculate its speed in km/h and m/s.

vi) How do forests help in maintaining the balance between oxygen and carbon Di oxide in atmosphere?

vii) List the different ways in which forests are useful to us.

9- Draw labelled diagram of any two of the following. (10)

i) Water cycle

ii) electric bulb

iii) rainwater harvesting