Physics-

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Easy

Question

# A bird in air is diving vertically over a tank with speed 5cm/s Base of the tank is silvered A fish in the tank is rising upward along the same line with speed 2cm/s Water level is falling at a rate of 2cm/s Speed of the image of fish formed after reflection in the mirror as seen by the bird in cm/s

- 8
- 6
- 3
- 4

## The correct answer is: 3

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### Consider the system of equations ax+by =0 , cx +dy=0 where a, b, c, d {0,1}

Statement ‐ I The probability that the system of equations has a unique solution is 3/8 Statement ‐ II The probability that the system has a solution is 1.

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### A bird in air is diving vertically over a tank with speed 5cm/s Base of the tank is silvered A fish in the tank is rising upward along the same line with speed 2cm/s Water level is falling at a rate of 2cm/s Speed of the image of fish as seen by the bird directly in cm/s is

### A bird in air is diving vertically over a tank with speed 5cm/s Base of the tank is silvered A fish in the tank is rising upward along the same line with speed 2cm/s Water level is falling at a rate of 2cm/s Speed of the image of fish as seen by the bird directly in cm/s is

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### A Ray of light goes from A in a medium where the speed of light is V_{1} to a point B in a medium where the speed of light is V_{2} as shown in figure The path of the rays as shown in figure Answer the following questions,based on the above paragraph The slope of curve is

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### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point Which of the following statements are correct regarding spherical aberration :

### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point Which of the following statements are correct regarding spherical aberration :

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### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point For paraxial rays, focal length approximately is

### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point For paraxial rays, focal length approximately is

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### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point The total deviation suffered by the ray falling on mirror at an angle of incidence equal to 60° is

### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point The total deviation suffered by the ray falling on mirror at an angle of incidence equal to 60° is

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### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point If f_{p} and f_{m} represent the focal length of paraxial and marginal rays respectively, then correct relationship is :

### Spherical aberration in spherical mirrors is a defect which is due to dependence of focal length ‘f’ on angle of incidence ‘ q ’ as shown in figure is given by where R is radius of curvature of mirror and q is the angle of incidence The rays which are closed to principal axis are called paraxial rays and the rays far away from principal axis are called marginal rays As a result of above dependence different rays are brought to focus at different points and the image of a point object is on a point If f_{p} and f_{m} represent the focal length of paraxial and marginal rays respectively, then correct relationship is :

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.

Hence,

Þ . Hence, element .

### The element in the first row and third column of the inverse of the matrix is

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Hence,

Þ . Hence, element .

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.

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attacks only carbonyl group and reduce it into alcohol group. They do not attack on double bond.

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