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Subject :NSO    Class : Class 9

Earthquakes generate sound waves inside the earth. Unlike a gas, the earth can experience both transverse S and longitudinal P sound waves. Typically the speed of S wave is about 4.0 km s-1, and that of P wave is 8.0 km s-1. A seismograph records P and S waves from an earthquake. The first P wave arrives 4 minutes before the first S wave. Assuming the waves travel in straight line, at what distance does the earthquake occur?

A 960 km
B 640 km
C 1920 km
D 2880 km


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Subject :NSO    Class : Class 9

Read the given statements and mark the correct option.
Statement 1 : Bohr's orbits are called stationary orbits.
Statement 2 : Electrons remain stationary in these orbits for some time.

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 9

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Subject :NSO    Class : Class 5

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Subject :NSO    Class : Class 4

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Subject :NSO    Class : Class 7

Ans 1:

Class : Class 7
The answer is c

Ans 2:

Class : Class 2

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Subject :NSO    Class : Class 7

Refer to the given figure of body cells and select the incorrect statements regarding X, Y and Z.

(i) Y maintains pH of blood.
(ii) Z is an important part of our immune system.
(iii) Z plays a key role in transporting gases in the blood.
(iv) The pigment present in X absorbs oxygen and transports it to the cells all over the body.

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


please explain

Ans 1:

Class : Class 8
in this case picture depict is wrong . WBC should be smaller than RBC in size .

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Subject :NSO    Class : Class 4

Ans 1:

Class : Class 4
d

Ans 2:

Class : Class 4
answer d

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Subject :NSO    Class : Class 10

A small conducting rod of length l, moves with a uniform velocity v in a uniform magnetic field B as shown in figure.


A The end X of the rod becomes positively charged.
B The end Y of the rod becomes positively charged.
C The entire rod is unerringly charged.
D The rod becomes hot due to joule heating.


By Fleming's right-hand rule, current flows from X to Y, but which end actually receives the extra positive charge?

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 6
See, Y is feeding on x which means that population of X would definitely decrease. This means that eater of water beetle has decreased. This indicates that population of water beetle will increase. This means more food for fro with beetle. with g. Due to large amount of food frogs' population will also increase parallelly. In this way B would be correct . Sorry for too long answer.

Ans 2:

Class : Class 6

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Subject :NSO    Class : Class 6

Ans 1:

Class : Class 6
C

Ans 2:

Class : Class 6

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