A compound microscope is an instrument that consists of two lenses L₁ and L₂. The lens L₁ called objective forms a real, inverted and magnified image of the given object. This serves as the object for the second lens L₂; the eyepiece. The eyepiece functions as a simple microscope or magnifier. It produces the final image, which is inverted with respect to the original object, enlarged and virtual.

What is the value and sign of magnification (according to the new Cartesian sign convention) of the image formed by L₁?

1. Value = Less than 1 and Sign = Positive
2. Value = More than 1 and Sign = Positive
3. Value = Less than 1 and Sign = Negative
4. Value = More than 1 and Sign = Negative

A compound microscope is an instrument that consists of two lenses L₁ and L₂. The lens L₁ called objective forms a real, inverted and magnified image of the given object. This serves as the object for the second lens L₂; the eyepiece. The eyepiece functions as a simple microscope or magnifier. It produces the final image, which is inverted with respect to the original object, enlarged and virtual.

If the power of the eyepiece (L₂) is 5 diopters and it forms an image at a distance of 80 cm from its optical centre, at what distance should the object be?

1. 12 cm
2. 16 cm
3. 18 cm
4. 20 cm

The figure shown below represents a common type of dialysis called as Haemodialysis. It removes waste products from the blood such as excess salts, and urea which are insufficiently removed by the kidney in patients with kidney failure. During the procedure, the patient's blood is cleaned by filtration through a series of semi-permeable membrane before being returned to the blood of the patient. On the basis of this, answer the following questions:

Which part of the nephron in human kidney, serves the function of reabsorption of certain substances?

1. Glomerulus
2. Bowman's capsule
3. Tubules
4. Collecting duct

A compound microscope is an instrument that consists of two lenses L₁ and L₂. The lens L₁ called objective forms a real, inverted and magnified image of the given object. This serves as the object for the second lens L₂; the eyepiece. The eyepiece functions as a simple microscope or magnifier. It produces the final image, which is inverted with respect to the original object, enlarged and virtual.

What types of lenses must be L₁ and L₂?

1. Both concave
2. Both convex
3. L₁ – concave and L₂– convex
4. L₁ – convex and L₂ – concave