Biological importance of Ozone layer is (a) It stops ultraviolet rays (b) Ozone rays reduce green house effect (c) Ozone layer reflects radio waves (d) Ozone layer controls radio in atmosphere

16 gm sample of a radioactive element is taken from Bombay to Delhi in 2 hour and it was found that 1 gm of the element remained (undisintegrated). Half life of the element is

(a) 2 hour

(b) 1 hour

(c)

(d)

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A nucleus of element X is represented as $^{56}_{26}\text{X}$
Which is an isotope of element X?

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The dielectric strength of a medium is $2 kV mm ^{-1}$ What is the maximum potential difference that can be established across a $50 \mu m$ sample without binding?

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Four wires each of length 2.0 metres are bent into four loops P, Q, R and S and then suspended into uniform magnetic field. Same current is passed in each loop. Which statement is correct

(a) Couple on loop P will be the highest	(b) Couple on loop Q will be the highest
(c) Couple on loop R will be the highest	(d) Couple on loop S will be the highest

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Two capacitances of capacity and are connected in series and potential difference V is applied across it. Then the potential difference across will be

(a)

(b)

(c)

(d)

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Reciprocal of Impedance is:

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Displacement current is continuous:

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Calculate the equivalent resistance between A and B

(a) W

(b) 3 W