Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

Which of the following is the purpose of an electrical cell?

  1. To change mechanical energy to electrical energy

  2. To change chemical energy to electrical energy

  3. To change electrical energy to mechanical energy

  4. To change electrical energy to chemical energy
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

An electrical cell is an "electrical power supply" - internally it converts stored chemical energy into electrical potential energy, allowing a current to flow from the positive terminal round to the negative one via an external circuit (this is called conventional current, which is chosen to go from + to -).

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

State whether true or false :

Do not connect the two terminals of a cell with a single wire.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

We should not connect the two terminals of the cell with a wire without an appliance connected in a circuit. This is because by doing so, chemicals in the cell gets used up quickly and after sometime cell will stop working.

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

 What are the three basic parts of a cell?

  1. Electrodes, electrolyte, container

  2. Electrodes, acid, water

  3. Anode, cathode, ions

  4. Anode, load, depolarize
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A cell is basically a source of energy or electrical energy; there are three basic things required to make a cell work.

$i)$ The source of energy,(electrolyte)
$ii)$ The conduction medium to transfer energy (electrodes)
$iii)$ The contained to stare the energy. 

Multiple choice physics chemical effects of electric current study about cells electric cell types of cells

How many different colors of wire are needed to ignite the bulb when connected with cell ?

  1. 2

  2. 1

  3. 4

  4. 6
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

There are two wires needed to connect and ignite the bulb when connected with cell.

$(i)$ To connect the terminal of the cell to the terminal of the bulb.
$(ii)$ The tungsten wire which will get lighten up.
Option $A$ is the correct answer. 

Multiple choice physics lens technical terms related to lens terms related to lenses introduction to lenses and its types

Which of the following term is not associated with a lens ?

  1. Aperture

  2. Focal length

  3. Principal focus

  4. Efficiency
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Aperture of a lens is the length of the surface of lens exposed for incident light.Focal length is the distance between focus of the lens and lens optical center.Principal focus is the focus from which a ray of light traveling parallel to optical axis passes through or appears to pass through after refraction.There is no term like efficiency of a lens.but there is magnification of a lens.

Multiple choice physics lens technical terms related to lens terms related to lenses introduction to lenses and its types

The value of the focal length of the lens is equal to the value of the image distance when the rays are

  1. Passing through the optic centre

  2. Parallel to the principal axis

  3. Passing throught he focus

  4. Over the mirror
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When the object is placed at infinity, i.e., when the rays are parallel to the principal axis, the value of focal length is equal to the value of the image distance.

i.e., object distance , $u=\infty$
From lens formula,

$\dfrac 1f=\dfrac 1u+\dfrac 1v\\\implies \dfrac 1f=\dfrac 1\infty+\dfrac 1v\\\implies f=v$
i.e., image distance is equal to focal length of the lens.