Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 10 Answered

Why do stars twinkle at night?Explain.
Asked by ashwati | 21 Feb, 2009, 09:43: PM
Expert Answer

The air near the earth being always in motion due to convection currents, its density does not remain constant at all the points, it goes on changing, even at points in the same level and therefore, the refractive index at different points goes on changing. So, the rays from a star  travelling in a given directiuon are somtimes concentrated at one point and sometimes at another which results in the twinkling of stars.

Answered by | 22 Feb, 2009, 12:16: PM

Application Videos

Concept Videos

Multiple Choice Questions Practice Test Subjective Questions Webinar Subjective Questions Pre Board Assessment
Answered Unanswered My Questions My Answers
CBSE 10 - Physics
What is reflection
Asked by vpitliya42 | 21 Nov, 2022, 01:21: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
If sun emmit yellow light so how it turns into white when it enters in earth atmosphere and if the question is ansewable then does it happens in other planets too
Asked by ak23012007 | 25 Oct, 2022, 09:50: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
An object at distance of 24cm is placed in front of Concave. mirror having focal length 10cm. find image distance. Nature of image and magnification
Asked by piustoppo9thb | 24 Jun, 2022, 09:58: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
if a plane mirror is rotated by an angle of theta by how much will the angle between the incident and the reflected ray change?
Asked by priyankakiran2017 | 22 Jun, 2022, 07:07: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
In recent days what alternative we used for silvering of mirror?
Asked by priyankakiran2017 | 21 Jun, 2022, 08:44: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
what is the cause of reflection of light
Asked by aarjugodara2 | 18 Jun, 2022, 04:36: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
It is desired to obtain an erect image of an object, using concave mirror of focal length of 15 cm. Where should we place the object? Where will the image of this object be, if it is placed at 30 cm in front of the mirror? Draw a ray diagram for this situation also to justify your answer.
Asked by malikanushka07 | 17 Jun, 2022, 02:18: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
we are unable to see our image in a plane mirror from every angle but we can see a chair in a room anywhere. Why?
Asked by priyankakiran2017 | 15 Jun, 2022, 03:26: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
A lens of focal length 12cm forms an erect image three times the size of the object. What is the distance between the object and image? 
Asked by bhu.joshi54 | 14 Jun, 2022, 09:21: PM
ANSWERED BY EXPERT
CBSE 10 - Physics
sir iska answer solve kr ke do
Asked by vaishnavimishra2003 | 14 Jun, 2022, 07:45: AM
ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get FREE Sample Mock Papers for Final Exams
Download Now
×