When an object is placed at the centre of curvature of a concave mirror the image formed is Mcq?

Last updated at Nov. 16, 2021 by Teachoo

(a) If the focal length of the concave mirror is 10 cm,  the image formed will be at a distance  ___________.  

(i) Between 10cm and 15cm  

(ii) Between 10cm and 20cm  

(iii) Beyond 20cm  

(iv) At 20 cm  

Ans. 

• As seen from the figure, the image formed is between focus and centre of curvature
• Thus, Image is formed between 10 and 20 cm.

So, the correct answer is (ii)

(b) In case of a concave mirror, the image distance is  _________ when image is formed in front of the  mirror and _________________ when the image  is formed behind the mirror.  

(i) positive, negative  

(ii) negative, negative 

(iii) negative, positive  

(iv) positive, positive  

Ans. 

According to the sign convention for concave mirror 

•  The image distance is negative when the image is formed in front of the mirror
•  The image distance is positive when the image   is formed behind the mirror . 

So, the correct answer is (iii) - negative, positive  

(c) If the size of the object in the given figure is 5 cm  and the magnification produced is –0.5. The size  of the image is (in cm) ___________  

(i) –2.5 

(ii) –0.1  

(iii) 2.5 

(iv) 0.1  

Ans.  

So, the correct answer is  (i) – 2.5 

(d) A negative sign in the magnification value  indicate that the image is  ____________   

(i) Real and inverted  

(ii) Real and erect  

(iii) Virtual and erect  

(iv) Virtual and inverted  

Ans.

So, the correct answer is (i) Real and inverted

(e) An image formed by concave mirror is virtual,  when the object is placed:  

(i) at infinity 

(ii) at C  

(iii) Between C and F 

(iv) Between P and F  

Ans. 

From figure we note that:

• If we place Object between P ole and F ocus
• Concave mirror forms virtual and erect images.

So, the correct answer is (iv) = Between P and F

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With the help of a ray diagram, determine the position, nature and size of the image formed of an object placed at the centre of curvature of a concave mirror. 

When an object is placed at the centre of curvature of a concave mirror, the image formed will be as shown: 

The image of an object placed at the centre of curvature of a concave mirror is real, inverted and of the same size as the object.

  Is there an error in this question or solution?

Page 2

Described with the help of a diagram, the nature, size and position of the image formed when an object is placed beyond the centre of curvature of a concave mirror.

The image formed by an object placed beyond the centre of curvature of a concave mirror is as follows: 

The above shows that the image formed by the concave mirror is

1. between the focus and centre of curvature
2. real and inverted
3. smaller than the object (or diminished)

  Is there an error in this question or solution?

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