Tag: physics

Quizzes (598) Questions (13441)

Questions Related to physics

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

Explore and answer :
Some children are playing in the playground. Suddenly clouds gather in the sky and there is thunder and lightning. What should they do now?
The children should_______.
Choose the correct answer.

  1. <span>Run to their houses&nbsp;</span>

  2. <span>Stand under a tree</span>

  3. <span>Just stand at their places&nbsp;</span>

  4. <span>Squat down</span>
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During a thunderstorm, the safest action is to seek shelter inside a sturdy building. Standing under trees or in open fields increases the risk of being struck by lightning.

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

Which of the following is safest way to protect yourself from lightning?

  1. Run to an open field

  2. Open an umbrella for cover

  3. Take shelter under a tree

  4. Squat low on ground
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

If caught outside during a lightning storm, squatting low on the ground minimizes your height and contact area with the ground, reducing the risk of being a target for a strike.

Multiple choice physics light and shadow formation of image by a pinhole camera pinhole camera shadow

Shadow formation is an example of :

  1. rectilinear propagation of light

  2. curvilinear propagation of light

  3. dispersion of light&nbsp;

  4. none of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Rayleigh Scattering is responsible for the formation of shadows which is phenomena of rectilinear propagation of light . Shadows are created when an object, animal or person blocks out a portion of a light source. Shadows form in the opposite direction of whatever is blocking that source.

Multiple choice physics light, shadows and images formation of image by a pinhole camera pinhole camera shadow

What is "Camera Obscura" effect ?

  1. Light from a scene passes through the aperture and gets reflected from the mirror placed at the other end of the box.

  2. Light from a scene passes from one medium to another and gets refracted

  3. Light from a scene passes through the aperture and passes through a lens placed on the opposite side of the box

  4. Light from a scene passes through the aperture and projects an inverted image on the opposite side of the box
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A pinhole camera is a simple camera without a lens but with a tiny aperture, a pinhole – effectively a light-proof box with a small hole in one side. Light from a scene passes through the aperture and projects an inverted image on the opposite side of the box, which is known as the camera obscura effect.

Multiple choice physics light and shadow formation of image by a pinhole camera pinhole camera shadow

A ray of sunlight enters a spherical water droplet $(n = \dfrac{4}{3})$ at an angle of incidence $53^\circ$ measured with respect to the normal to the surface. It is reflected from the back surface of the droplet and re-enters into air. The angle between the incoming and outgoing ray is [Take $\sin \ 53^\circ = 0.8$]

  1. $15^\circ$

  2. $127^\circ$

  3. $138^\circ$

  4. $30^\circ$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The angle between the incoming and outgoing ray is $180^o-53=127$.