Quiz for Ray Optics

Q1: What is the focal length of a plane mirror?

A. Infinity B. Zero C. One meter D. Depends on object distance

Q2: The image formed by a concave mirror is virtual, erect and magnified. The object is placed:

A. At focus B. Between focus and pole C. Beyond center of curvature D. At center of curvature

Q3: Mirror formula is given by:

A. 1/f = 1/u - 1/v B. f = 1/u + 1/v C. 1/f = 1/v + 1/u D. 1/f = 2u - v

Q4: Refractive index is defined as:

A. c/v B. v/c C. 1 + c/v D. c + v

Q5: Total internal reflection occurs when:

A. Light goes from rarer to denser medium B. Incident angle is less than critical angle C. Light goes from denser to rarer medium and angle is more than critical angle D. Light falls normally

Q6: The power of a lens is measured in:

A. Meters B. Centimeters C. Diopters D. Joules

Q7: Which type of mirror is used in car headlights?

A. Concave B. Convex C. Plane D. Combination

Q8: A convex lens of focal length 20 cm is placed in air. What is its power?

A. +2 D B. +5 D C. -5 D D. 0.5 D

Q9: Which of the following is not a property of image formed by plane mirror?

A. Virtual B. Inverted C. Same size as object D. Erect

Q10: The critical angle for total internal reflection depends on:

A. Wavelength of light B. Density of medium only C. Angle of incidence only D. Refractive index of both media

Q11: Which mirror always forms a virtual, diminished image?

A. Concave B. Convex C. Plane D. Parabolic

Q12: A real and inverted image is formed by a convex lens when object is placed:

A. Between lens and focus B. At focus C. Beyond 2F D. Between focus and 2F

Q13: If a ray passes undeviated through a lens, it must be:

A. Parallel to principal axis B. Through the optical center C. Along focal point D. At an angle

Q14: In lens formula 1/f = 1/v - 1/u, u is:

A. Focal length B. Image distance C. Object distance D. Radius of curvature

Q15: Which of the following instruments works on total internal reflection?

A. Prism B. Spectrometer C. Periscope D. All of these

Q16: The magnification produced by a mirror is negative for:

A. Virtual image B. Real image C. Erect image D. Plane mirror

Q17: A convex lens forms a real image only when object is:

A. Between optical center and focus B. At focus C. Beyond focal point D. At optical center

Q18: If power of a lens is -4 D, it is a:

A. Convex lens B. Concave lens C. Plane mirror D. Cylindrical lens

Q19: A convex mirror is preferred as rear-view mirror because:

A. Forms real images B. Wider field of view C. Magnifies image D. Gives depth

Q20: Which lens is used to correct myopia?

A. Convex B. Concave C. Cylindrical D. Plano-convex