Current Electricity — Physics STD 10 — Question

Which characteristic property of light is responsible for the blue colour of the sky?

A lens forms an upright and magnified image of an object name the lens

Name the material prism required for obtaining the spectrum of infra red radiation.

Calculate the force which will produce a moment of force of 1575 dyne-cm, when the perpendicular distance between point of application of force and turning point is 45 cm.

A coolie, with a load of 30 kg on his head, walks on the platform. If he walks a distance of 60 m, what is the work done by him?

Write the approximate value of the speed of sound in air.

Name a machine to obtain gain in speed ?

What is the work done on a body by the gravitational force towards the centre of the path acting when it moves along a circular path?

What are the ultrasonic waves?

Which of the cables, one rated 5 A and the other 15 A will be of thicker wire? Give a reason for your answer.