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Class 10th English medium science objective questions
Science
Some Important questions
Q1. Which type of mirror is used during shaving?
(a.) Plane,
(b.) Concave,
(c.) Convex,
(d.) None of these.
Answer:- (b.) Concave
Q2. The relation between focal length and radius of curvature in a spherical mirror is.
a.) r=f/2
b.) f=r/2
C.) r=f
d ) None of them
Answer (b.) f=r/2
Q3. Which physical quantity remains unchanged during refraction of light?
(a.) Frequency,
(b.) Velocity,
(c.) Wave length,
(d.) None of these.
Answer:- (a.) Frequency
Q4. How many laws of reflection of light are there?
a) One
b.) Two
c.) Three
d). Four
Answer:- (b.) Two
Q5. The part of human eye on which image of an object has formed is-
a.) Cornea
b.) Iris
c.) Pupil
d.) Retina
Answer:- (d.) Retina.
Q6. What is the near point of common eye?
a.) 10cm
b.) 20cm
c.) 25cm
d.) 1m
Answer - (c.) 25cm
Q7. What will be the nature of images in human eye?
a.) Erect, virtual
b.) Inverted, virtual
c.) Erect, real
d.) Inverted, real
Answer – (d.) Inverted, real
Q8. Light rays move in –
a.) Straight line
b.) Curved line
c.) Any direction
d.) All of these
Answer - (a.) Straight line
Q9. What is the unit of power of Lens?
a.) Meter
b.) Centimetre
c.) Diopter
d.) None of these
Answer – (c.) Diopter.
Q10. What is the far point of a common eye?
a.) 20cm
b.) 25cm
c.) 50cm
d.) Infinity
Answer - (d.) Infinity
Chapter wise objective questions class 10th
Science
Chapter 10
Light -Reflection and Refraction
Q 1. Focal length of plane mirror is
a. At infinity
b. Zero
c. Negative
d. None of these
Answer A.) At infinity
Q 2. Image formed by plane mirror is
a. Real and erect
b. Real and inverted
c. Virtual and erect
d. Virtual and inverted
Answer C.) Virtual and erect
Q 3. A concave mirror gives real, inverted and same size image if the object is placed
a. At F
b. At infinity
c. At C
d. Beyond C
Answer C.) At C
Q 4. Power of the lens is -40, its focal length is
a. 4m
b. -40m
c. -0.25m
d. -25m
Answer C) -0.25m
Q 5. A concave mirror gives virtual, refract and enlarged image of the object but image of smaller size than the size of the object is
a. At infinity
b. Between F and C
c. Between P and F
d. At E
Answer C) Between P and F
Q 6. In optics an object which has higher refractive index is called
a. Optically rarer
b. Optically denser
c. Optical density
d. Refractive index
Answer B) Optically denser
Q 7. The optical phenomena, twinkling of stars, is due to
a. Atmospheric reflection
b. Total reflection
c. Atmospheric refraction
d. Total refraction
Answer C.) Atmospheric refraction
Q 8. Convex lens focus a real, point sized image at focus, the object is placed
a. At focus
b. Between F and 2F
c. At infinity
d. At 2F
Answer C.) At infinity
Q 9. The unit of power of lens is
a. Metre
b. Centimeter
c. Diopter
d. M-1
Answer C) Diopter
Q 10. The radius of curvature of a mirror is 20cm the focal length is
a. 20cm
b. 10cm
c. 40cm
d. 5cm
Answer B.) 10cm
