1) The volume of sphere V = (4/3) πR3 . Find the rate of change of volume with respect to R ?

1 ) The volume of sphere  V = (4/3) πR³ . Find the rate of change of volume with respect to R ?      ( R = radius of sphere )

Solution : -

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2 ) Two parallel wires  , one of length of 1 m and other is infinitive , are lying at a distance of 2 m . If the current flowing in each wire is 1 ampere , then force between them will be : -

A ) 10 N ,                                                   B ) 10 ^ (-7) N ,

C ) 10 ^ (-14) N ,                                        D ) None of these ,

Correct Answer : -   B ) 10 ^ (-7) N ,

Solution : -

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3 ) The unit of electric current  ‘ ampere ’ is the amount of current flowing through each of two parallel wires 1 m apart and of infinite length will give rise to a force between them equal to : -

A ) 10 N ,                                                   B ) 2 x 10 ^ (-7) N ,

C ) 10 ^ (-14) N ,                                        D ) None of these ,

Correct Answer : -   B ) 2 x 10 ^ (-7) N ,

Solution : -

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