# Optics

Rajat asked: “when we exchange the lenses of compound microscope, then why it does not act as a telescope?”

# LIGHT –REFLECTION AND REFRACTION QUESTIONS TO PRACTICE

LIGHT –REFLECTION AND REFRACTION QUESTIONS TO PRACTICE 1. What are the differences between real image and virtual image? 2. The radius of curvature of a concave mirror is -46cm.What is its focal length? 3. How will you identify a plane mirror, a concave mirror and a convex mirror without touching their surface? 4. Which mirror … Continue reading LIGHT –REFLECTION AND REFRACTION QUESTIONS TO PRACTICE

# Why the ray of light passing through optical center of a lens passes undeviated while when it passes through other points on the interface of the lens, it gets refracted?

Deviation is the change in direction of the ray while passing through the lens. The middle portion of the lens is comparatively flat and there is a point on the principal axis and inside the sphere through which all the undeviated rays pass. “Undeviated” doesn’t mean that there is no refraction. When we say that … Continue reading Why the ray of light passing through optical center of a lens passes undeviated while when it passes through other points on the interface of the lens, it gets refracted?

# Why the ray of light passing through the centre of curvature of a concave mirror behave as normal while it doesn’t behave as normal when it passes through other points on the principal axis?

Remember that a concave mirror forms part of a hollow sphere. Any line joining the centre of the sphere (the centre of curvature of the mirror) and any point on the mirror will be normal to the reflecting surface of the mirror. Therefore A ray of light passing through the principal axis will be normal … Continue reading Why the ray of light passing through the centre of curvature of a concave mirror behave as normal while it doesn’t behave as normal when it passes through other points on the principal axis?

# When several transparent materials are kept above each other, the resultant behaves like an opaque object.Why?What’s the Optics behind it?

When light falls on a object, three things happen - A part of the light is absorbed Another part is reflected ad The remaining part is transmitted. A transparent medium transmits most of the light incident on it. However, it absorbs a small part as well as reflect a small part. Therefore, when a number … Continue reading When several transparent materials are kept above each other, the resultant behaves like an opaque object.Why?What’s the Optics behind it?

# Questions received from a curious UG student

I have several doubts in physics.Would you like to answer me please?The following are the doubtful questions I have - 1.What is meant by 'Radic'? 2.What is a 'parallelopiped'?Is it a 3-dimensional parallelogram? 3.Why does no electric current flow through vacuum? 4.When several transparent materials are kept above each other, the resultant behaves like an … Continue reading Questions received from a curious UG student