A student focussed the image of a distant object using a device X on a white screen S as shown in the figure. If the distance of the screen from the device is 30 cm, select the correct statement about the device X.
A. The device X is a concave mirror of focal length 15 cm.
B. The device X’ is a concave mirror of focal length 30 cm.
C. The device X is a concave mirror of radius of curvature 30 cm.
D. The device X is a convex mirror of focal length 30 cm.
Answer:B
A student focussed the image of a distant object using a device X on a white screen S as shown in the figure. If the distance of the screen from the device is 30 cm, select the correct statement about the device X.
A. The device X is a concave mirror of focal length 15 cm. B. The device X’ is a concave mirror of focal length 30 cm. C. The device X is a concave mirror of radius of curvature 30 cm. D. The device X is a convex mirror of focal length 30 cm.
Explanation: Concave mirror is a converging mirror and the distance between mirror and screen is focal length.