Advertisements
Advertisements
प्रश्न
_______ is a combination of two convex lenses with small focal length.
पर्याय
simple microscope
compound microscope
telescope
none of these
Advertisements
उत्तर
Compound microscope is a combination of two convex lenses with small focal length.
APPEARS IN
संबंधित प्रश्न
A student focuses the image of a well-illuminated distant object on a screen using a convex lens. After that, he gradually moves the object towards the lens and each time focuses its image on the screen by adjusting the lens.
(i) In which direction, towards the screen or away from the screen, does he move the lens?
(ii) What happens to the size of the image? Does it decrease or increase?
(iii) What happens to the image on the screen when he moves the object very close to the lens?
A student has obtained a magnified image of a flame on a screen using a convex lens. To draw the corresponding ray diagram to show the image formation, which of the following two rays whose paths after refraction are shown, should he select ?
(A) I and II
(B) II and III
(C) III and IV
(D) I and III
A 1 cm high object is placed at a distance of 2f from a convex lens. What is the height of the image formed?
Explain with the help of a diagram, why the convex lens is also called a converging lens.
Define principal axis, principal focus and focal length of a convex lens.
Draw a ray diagram to show the formation of a real magnified image by a convex lens. (In your sketch the position of object and image with respect to the principal focus of lens should be shown clearly).
In order to obtain a real image twice the size of the object with a convex lens of focal length 15 cm, the object distance should be:
(a) more than 5 cm but less than 10 cm
(b) more than 10 cm but less than 15 cm
(c) more than 15 cm but less than 30 cm
(d) more than 30 cm but less than 60 cm
Which part causes the greatest convergence?
In a certain murder investigation, it was important to discover whether the victim was long-sighted or short-sighted. How could a detective decide by examining his spectacles?
The diagram alongside shows the refraction of a ray of light from sir to a liquid.
(a) write the values of (i) angle of incidence, (ii) angle of refraction.
(b) use snell’s law to find the refractive index of liquid with respect to air.
A light ray does not bend at the boundary in passing from one medium to the other medium if the angle of incident is:
A parallel oblique beam of light falls on a convex lens. Draw a diagram to show the refraction of light through the lens.
What is the difference between a double convex and a bi-convex lens?
Point out the difference between a convex lens and a concave lens.
State the nature and position of the object on the principal axis to obtain a virtual and magnified image.
Draw a diagram to show the convergent action of a convex lens by treating it as a combination of glass block and two triangular glass prisms, with the aid of two parallel incident rays.
Diagram shows an object AB placed on the principal axis B of a convex lens placed in air. F1 and F2 are the two foci of the lens.
(i) Copy the diagram:
Draw a ray of light starting from B and passing through O. Show the same ray after refraction by the lens. Draw another ray from B which passes through F2 after refraction by the lens. Locate the final image
(ii) Is the image real or virtual?
Which of the following statements is true?
