Science
Assertion (A) : A convex mirror always forms an image behind it and the image formed is virtual.
Reason (R) : According to the sign convention, the focal length of a convex mirror is positive.
options
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Reflection of Light
2 Likes
Answer
Both A and R are true, and R is not the correct explanation of A.
Reason —
Assertion (A) is true because the reflected rays from a convex mirror diverge and when extended backward, they appear to meet at a point behind the mirror. Therefore, the image formed is always virtual, erect, and diminished, regardless of the object’s position.
Reason (R) is true because by convention, distances measured in the direction of the incident light are taken as positive and the focus of a convex mirror lies on the same side as the incident light, hence its focal length is positive.
Hence, both A and R are true, and R is not the correct explanation of A.
Answered By
3 Likes
Related Questions
Assertion (A) : On adding dil. HCl to a test tube containing a substance ‘X’, a colourless gas is produced which gives a pop sound when a burning match stick is brought near it.
Reason (R) : In this reaction metal ‘X’ is displaced by Hydrogen.
options
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A) : Generally, the number of chromosomes in a cell and in a germ cell is not the same in species.
Reason (R) : When two germ cells combine, they restore the normal number of chromosomes in a species.
options
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Assertion (A) : If the lions are removed from a food chain it will not affect the food chain, however if the plants are removed from a food chain it will disturb the ecosystem.
Reason (R) : Plants are producers who can make food using sunlight, while lions are consumers.
options
- Both A and R are true, and R is the correct explanation of A.
- Both A and R are true, and R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Identify the type of each of the following reactions stating the reason for your answers.
(a) Fe2O3 + 2Al → Al2O3 + 2Fe + heat
(b) Pb(NO3)2 + 2KI → PbI2(↓)+ 2KNO3