MEDIUM
10th CBSE
IMPORTANT
Earn 100

A convergent lens of power 8 D is combined with a divergent lens of power -10 D. Calculate focal length of the combination.

Important Questions on Light - Reflection and Refraction

MEDIUM
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>PROBLEMS FOR PRACTICE>Q 10
Convex lens of focal length 20 cm and concave lens of focal length 10 cm are placed in contact. Calculate (i) Total power of combination, (ii) What is the nature of the combination.
EASY
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 1
A student obtained a sharp image of the grill of a window on a screen, using a convex lens. For getting better results, the teacher suggested focusing a distant tree instead of the grill. In which direction should the lens be moved for this purpose? 
EASY
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 2
Give the diagram which represents the correct angle of incidence i, angle of refraction r and angle of emergence e for the experiment tracing the path of a ray of light passing through a rectangular glass slab.
EASY
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 3
State the law of refraction.
EASY
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 4
Define power of a lens. What is its unit?
MEDIUM
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 5
State the uses of a convex lens. 
MEDIUM
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 6
The power of a lens is -4 D. What is the focal length? Is the lens convex or concave?
MEDIUM
10th CBSE
IMPORTANT
Science Part-I NEW ERA PHYSICS Textbook for Class X>Chapter 4 - Light - Reflection and Refraction>Test Your Self Exercise 2>Q 7
Calculate the distance at which an object should be placed in front of a convex lens of focal length 20 cm to obtain an image double its size.