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Subject :NSO    Class : Class 8

Read the given statements and select the correct option.
Statement 1 : Silver objects become green and lose their shine with the passage of time.
Statement 2 : Silver reacts with carbon dioxide and moisture present in the atmosphere.

A Both statements 1 and 2 are true and statement 2 is the correct explanation of statement 1.
B Both statements 1 and 2 are true but statement 2 is not the correct explanation of statement 1.
C Statement 1 is true and statement 2 is false.
D Both statements 1 and 2 are false.


Ans 1:

Class : Class 8
ans D is the correct answer as silver turns black after reaction to hydrogen sulphide

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 7
20 mL multiplied by 10 equals 200 ml.. likewise, multiply 1 min by 10. the answer is 10 minutes or 600 seconds.

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Subject :NSO    Class : Class 3

Sheetal has taken an empty bottle and fixed a deflated balloon on its mouth. She placed the bottle in a container filled with hot water. After some time, the balloon gets inflated as shown. What could be the most appropriate reason for this?


A Air when gets heated becomes heavier and rises up.
B Air when gets heated becomes lighter and settles down.
C Air when gets heated becomes heavier and settles down.
D Air when gets heated becomes lighter and rises up.


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Subject :NSO    Class : Class 5

Ans 1:

Class : Class 5
a b c d

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Subject :NSO    Class : Class 9

A particle moves on a circular path of radius 7 m with uniform speed of 11 m/s. If it reaches point T from point S, a diametrically opposite point, then during this interval

(i) The average acceleration is zero.
(ii) The average velocity is zero.
(iii) The average acceleration is 11 m/s2.
(iv) The average velocity is 7 m/s.
Which of the following options is correct?

A(i) and (ii) only
B(ii) and (iii) only
C(iii) and (iv) only
D(i) and (iv) only


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Subject :NSO    Class : Class 9

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Subject :NSO    Class : Class 9

A cricket ball of mass 150 g moving with a speed of 126 km/h hits at the middle of the bat, held firmly at its position by the batsman. The ball moves straight back to the bowler after hitting the bat. Assume that the ball rebounds with same speed and they remain in contact for 0.001 s, the force that the batsman had to apply to hold the bat firmly at its place would be

A10.5 × 10-4 N
B2.1 × 103 N
C1.05 × 104 N
D2.1 × 104 N


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Subject :NSO    Class : Class 9

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Subject :NSO    Class : Class 9

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Subject :NSO    Class : Class 9

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