Class 10 Physics11)
If a man’s face is 25 cm in front of concave shaving mirror producing erect image 1.5 times the size of face, focal length of the mirror would be
In concave shaving mirror, virtual erect and large size image, behind the mirror is obtained, using
Class 10 Physics12)
As light travels from a rarer to a denser medium it will have
both (b) and (c)
When light ray travel from rarer to denser medium, its velocity and wavelength both decrease as v = vλ.
Class 10 Physics13)
The angle of incidence i and refraction r are equal in a transparent slab when the value of i is
depend on the material of the slab
When the incident ray falls normally on the glass slab, it will refracted without deviation, i.e. along the normal in the glass slab. So, ∠i = ∠r = 0
Class 10 Physics14)
The refractive index of transparent medium is greater than one because
Speed of light in vacuum > speed of light in tansparent medium
Class 10 Physics15)
You are given three media A, B and C of refractive index 1.33, 1.65 and 1.46. The medium in which the light will travel fastest is
So, the light will travel faster in a medium having lower refractive index.
Class 10 Physics16)
Light from the Sun falling on a convex lens will converge at a point called
The parallel ray coming from the sun, after refraction through the convex lens converge at its focus.
Class 10 Physics17)
A divergent lens will produce
always virtual image
Diverging (concave) lens will always forms a virtual, erect and diminished image.
Class 10 Physics18)
When object moves closer to convex lens, the image formed by it shift
away from the lens
As object moves from infinity towards optical centre of the convex lens image is shifted away from its focal point and towards infinity.
Class 10 Physics19)
When object moves closer to a concave lens the image by it shift
toward the lens
When object infinity, image is formed at the focus of concave lens of object is moved towards lens, the image is also moved from its focus towards lens and its size increase.
Class 10 Physics20)
A magnified real image is formed by a convex lens when the object is at
(a) and (b) both
When object is at 2F, real inverted and same size image is formed by convex lens. So, according to question option (a) and (b) both are correct.