An object is placed \(20\) cm in front of a concave mirror of a radius of curvature \(10\) cm. The position of the image from the pole of the mirror is:
1. \(7.67\) cm
2. \(6.67\) cm
3. \(8.67\) cm
4. \(9.67\) cm
1. | smaller in size. |
2. | inverted. |
3. | between the focus and centre of curvature. |
4. | All of the above. |
(A) | Incident rays travelling parallel to the principal axis always pass through \(F\) after reflection. |
(B) | Incident rays passing through \(F\) always travel parallel to the principal axis after reflection. |
(C) | The image formed is always inverted. |
(D) | The image formed is always real. |
(E) | The image formed is always larger than the object. |
1. | (A) and (C) only |
2. | (C), (D) and (E) only |
3. | (B) and (D) only |
4. | (A) and (B) only |
Column 1 | Column 2 | ||
A. | \(m= -2\) | I. | convex mirror |
B. | \(m= -\frac{1}{2}\) | II. | concave mirror |
C. | \(m= +2\) | III. | real Image |
D. | \(m= +\frac{1}{2}\) | IV. | virtual Image |
A | B | C | D | |
1. | I & III | I & IV | I & II | III & IV |
2. | I & IV | II & III | II & IV | II & III |
3. | III & IV | II & IV | II & III | I & IV |
4. | II & III | II & III | II & IV | I & IV |
1. | \(f' = f\) |
2. | \(f'<f\) |
3. | \(f'>f\) |
4. | The information is insufficient to predict |
A \(4.5~\text{cm}\) needle is placed \(12~\text{cm}\) away from a convex mirror of focal length \(15~\text{cm}\). What is the magnification?
1. \(0.5\)
2. \(0.56\)
3. \(0.45\)
4. \(0.15\)
1. | \(10\) cm | 2. | \(15\) cm |
3. | \(20\) cm | 4. | \(30\) cm |
A convex mirror of focal length \(f\) forms an image which is \(\frac{1}{n}\) times the length of the object. The distance of the object from the mirror is:
1. \((n-1)f\)
2. \(\left( \frac{n-1}{n} \right)f\)
3. \(\left( \frac{n+1}{n} \right)f\)
4. \((n+1)f\)
1. | \(10\) cm | 2. | \(15\) cm |
3. | \(2.5\) cm | 4. | \(5\) cm |
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. | \(\dfrac{f}{4}\) |