September 21, 2021
September 20, 2021
A person is standing at the sea shore. An observer on the ship which is anchored in between a vertical cliff and the person on the shore fires a gun. The person on the shore hears two sounds, 2 seconds and 3 seconds after seeing the smoke of the fired gun. If the speed of sound in the air is 320 ms-1 then calculate:
September 19, 2021
The diagram above shows a wire stretched over a sonometer. Stems of two vibrating tuning forks A and B are touched to the wooden box of the sonometer. It is observed that the paper rider (a small piece of paper folded at the centre) present on the wire flies off when the stem of vibrating tuning fork B is touched to the wooden box but the paper just vibrates when the stem of vibrating tuning fork A is touched to the wooden box.
September 18, 2021
Draw the diagram of a right angled isosceles prism which is used to make an inverted image erect.
September 17, 2021
An object is placed at a distance of 12 cm from a convex lens of focal length 8 cm. Find:
September 16, 2021
An object AB is placed between O and F1 on the principal axis of a converging lens as shown in the diagram.
Copy the diagram and by using three standard rays starting from point A, obtain an image of the object AB.
September 15, 2021
A ray of light XY passes through a right angled isosceles prism as shown below.
September 14, 2021
September 13, 2021
A half metre rod is pivoted at the centre with two weights of 20 gf and 12 gf suspended at a perpendicular distance of 6 cm and 10 cm from the pivot respectively as shown below.
September 12, 2021
September 11, 2021
State any two advantages of electromagnets over permanent magnets.