A ray of light is incident on an equilateral glass prism placed on a horizontal table as shown. For minimum deviation, a true statement is:
1. | \(PQ\) is horizontal |
2. | \(QR\) is horizontal |
3. | \(RS\) is horizontal |
4. | Either \(PQ\) or \(RS\) is horizontal |
1. | \(\frac{\sqrt{3}}{2} \) | 2. | \(1.5 \) |
3. | \(1.732 \) | 4. | \( 2\) |
A thin rod of length \(\frac{f}{3}\) lies along the axis of a concave mirror of focal length \(f\). One end of its magnified, real image touches an end of the rod. The length of the image is:
1. | \(f\) | 2. | \(\dfrac{f}{2}\) |
3. | \(2f\) | 4. | \(\dfrac{f}{4}\) |
A thin equiconvex lens of power \(P\) is cut into three parts \(A,B,\) and \(C\) as shown in the figure. If \(P_1,P_2\) and \(P_3\) are powers of the three parts respectively, then:
1. | \(P_1=P_2=P_3\) | 2. | \(P_1>P_2=P_3\) |
3. | \(P_1<P_2=P_3\) | 4. | \(P_2=P_3=2P_1\) |
A point source of light \(B\) is placed at a distance \(L\) in front of the centre of a mirror of width \(d\) hung vertically on a wall. A man \((A)\) walks in front of the mirror along a line parallel to the mirror at a distance \(2L\) from it as shown. The greatest distance over which he can see the image of the light source in the mirror is:
1. \(\frac{d}{2}\)
2. \(d\)
3. \(2d\)
4. \(3d\)
1. | \(32.75\) | 2. | \(327.5\) |
3. | \(0.3275\) | 4. | None of the above |
A medium shows relation between \(i\) and \(r\) as shown. If the speed of light in the medium is \(nc\) then the value of \(n\) is:
1. | \(1.5\) | 2. | \(2\) |
3. | \(2^{-1}\) | 4. | \(3^{-\frac{1}{2}}\) |
1. | lies between \(\sqrt{2} \text { and } 1 \text {. }\) |
2. | lies between \(2\) and \(\sqrt{2} \) |
3. | is less than \(1\). |
4. | is greater than \(2\). |
1. | \(-10\) cm | 2. | \(20\) cm |
3. | \(-30\) cm | 4. | \(5\) cm |