MEDIUM
10th CBSE
IMPORTANT
Earn 100

Find the power (in D) of a concave lens of focal length 3 m.

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Important Questions on Reflection and Refraction

MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 4
An object is placed 60 cm from a concave lens. The image is formed at a distance of 20 cm from the optical centre. Find the focal length of the lens. Is the lens converging or diverging?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 5
A convex lens is of focal length 30 cm. Find the distance where the object should be placed in front of the lens so that the image is formed 10 cm from the lens. What is the magnification?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 6
A 10 cm high object is placed at a distance of 30 cm from a convex lens of focal length 10 cm. Draw a ray diagram and find the position, size and nature of image formed.
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 7
A convex lens of focal length 18 cm and a concave lens of focal length 24 cm are placed in contact such that they have a common principal axis. Find the power of their combination. Will the combination behave as a converging or diverging lens?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 8
To find the image distance for varying object distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that, he gradually moves the object towards the lens and each time focuses its image on the screen.
In which direction - towards or away from the lens, does he move the screen to focus the object?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 8
To find the image distance for varying object distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that, he gradually moves the object towards the lens and each time focuses its image on the screen.
What happens to the size of image - does it increase or decrease?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 8
To find the image distance for varying object distances in case of a convex lens, a student obtains on a screen a sharp image of a bright object placed very far from the lens. After that, he gradually moves the object towards the lens and each time focuses its image on the screen.
What happens when he moves the object very close to the lens?
MEDIUM
10th CBSE
IMPORTANT
Modern's ABC+ Of Science Physics>Chapter 4 - Reflection and Refraction>Practice Exercise 4D>Q 9
"A convex lens can form a magnified, erect as well as inverted image of an object placed in front of it”. Draw ray diagram to justify this statement stating the position of the object with respect to the lens in each case.