Tag: some natural phenomena

Quizzes (10) Questions (151)

Questions Related to some natural phenomena

Multiple choice physics some natural phenomena lightning conductors lightning safety advanced of lightning

Which one of the following statements is CORRECT?

    1. Lightning rods are made of insulators

    2. A conductor holds charge

    3. The earth is an insulator

    4. An insulator prevents charge from flowing
    Reveal answer Fill a bubble to check yourself
    D Correct answer
    Explanation

    An insulator does not allow the electric current to flow through it. Insulator offers very high resistance to the flow of electric current (charge).

    Multiple choice physics some natural phenomena lightning conductors lightning safety advanced of lightning

                          is engineered to protect an elevated structure in the event of lightning strike.

    1. A lightning conductor

    2. Copper wire

    3. A lightening shield

    4. All of the above
    Reveal answer Fill a bubble to check yourself
    A Correct answer
    Explanation

    A lightening conductor is a metal rod mounted on a structure and designed to protect the structure from lightening strike. 

    Multiple choice physics some natural phenomena lightning conductors lightning safety advanced of lightning

    If the instantaneous current in a metallic wire is $i = \left( {5 + 10t} \right)A$ then find amount of charge flown through it from $t = 2s$ to $t = 3s$ is

    1. 10 C

    2. 20 C

    3. 30 C

    4. 40 C
    Reveal answer Fill a bubble to check yourself
    C Correct answer
    Explanation

    Given instantaneous current,

    $i=(5+10t)A$
    and from the definition of instantaneous current,  $i=\dfrac { dq }{ dt } $
    $\Rightarrow \quad \left( 5+10t \right) =\dfrac { dq }{ dt } $
    $dq=\left( 5+10t \right) dt$
    Integrating implies,
    $Q=5t+{ 5t }^{ 2 }$
    At $t=2$,
                    ${ Q } _{ 1 }=30C$
    At $t=3$,
                    ${ Q } _{ 2 }=60C$

    $\therefore $  Option (C) is the correct option.

    Multiple choice physics some natural phenomena transfer of charge types of charges and their interaction transfer of charges

    What happens when the end of the paper clip of electroscope is touched by hands?

    1. Electric current is produced 

    2. Foil strips remain as it is

    3. Foil strips collapse

    4. None of the above
    Reveal answer Fill a bubble to check yourself
    C Correct answer
    Explanation

    Because the charges on foil strips gets discharge through air body as soon as paper clip of electroscope is touched by hand, the foil strips collapse.

    Multiple choice physics some natural phenomena transfer of charge types of charges and their interaction transfer of charges

    Opening up of strips of an electroscope is an indication of:

    1. proximity of a conductor.

    2. proximity of a charged body.

    3. proximity of an uncharged body.

    4. earth connection.
    Reveal answer Fill a bubble to check yourself
    B Correct answer
    Explanation

    When a charged body comes close to an electroscope, charges are induced to the electroscope. These charges flow down to the metal strips which open up due to repulsion for having similar charges.