Question 2 :
If a $3cm$ tall object placed perpendicular to principal axis of a convex lens of focal length $15cm$ produces a real invented image of height $15cm$, then its object distance $(u)$ is ................ and image distance $(v)$ is ................
Question 4 :
The power of a lens having a focal length of $1 cm$ is :<br/>
Question 5 :
If the power of a lens is $0.1\;D$, its focal length is
Question 6 :
A convex lens of focal length 80 cm and concave lens of focal length 50 cm are combined together. What will be their resultant power?<br>
Question 7 :
A ray of light in a liquid of refractive index 1.4, approaches the boundary surface between the liquid and air at an angle of incidence whose sine is 0.8. Which of the following statements is correct about the behaviour of the light
Question 8 :
The apparent flattening of the sun at sunset and sunrise is due to
Question 9 :
Power of a lens is -40 , its focal length is
Question 10 :
The distance between an object and a divergent lens is $m$ times the focal length of the lens. The linear magnification produced by the lens is
Question 11 :
The lens of a simple magnifier has a focal length of 2.5 cm. Calculate the angular magnification produced when (a) the image is at least distance of distinct vision, and (b) infinity.
Question 13 :
The focal length of a concave mirror is $50\ cm.$ Where an object beplaced so that its image is two times and inverted
Question 14 :
A convex lens has focal length $30$cm. If an object is placed at a distance of $15$cm from it then the magnification produced by the lens is?
Question 15 :
What would you use to obtain a real and inverted image for any position of an object ?
Question 16 :
A short linear object of length $b$ lies along the axis of a concave mirror of focal length $f$ at a distance $u$ from the pole of the mirror. The size of the image is approximately equal to:<br/>
Question 17 :
A $4.5 cm$ needle is placed $12 cm$ away from a convex mirror of focal length $15 cm$. Find the location of the image and the magnification.
Question 18 :
An image of a bright square is obtained on a screen with the aid of a convergent lens. The distance between the square and the lens is $40\ cm$. The area of the image is nine times larger than that of the square. Select the correct statement(s).
Question 19 :
What happens when a ray of light is made to fall on a mirror along the normal?<br/>
Question 20 :
The image obtained while finding the focal length of convex lens is...................
Question 21 :
A $2.5$ dioptre lens forms a virtual image which is $4$ times the object placed perpendicularly on the lens. Then the required distance of the object from the lens is .
Question 22 :
Let the x-z plane be the boundary between two transparent media. Medium $1$ in $z\ge 0$ has a refractive index of $\sqrt { 2 } $ and medium $2$ with $z< 0$ has refractive index of $\sqrt { 3 } $. A ray of light in medium $1$ given by the vector $\vec { A } =6\sqrt { 3 } \hat { i } +8\sqrt { 3 } \hat { j } -10\hat { k } $ is incident on the plane of separation. The angle of refraction in medium $2$ is:
Question 23 :
Air has refractive index $1.0003$. Find the thickness of air column which will contain one more wavelength of yellow light of $6000$ $A^0$ than in same thickness of vacuum.
Question 24 :
Two thin lenses of power $+3.5D, -2D$ are placed in contact. Find the power of lens combination.
