Systems of Particles and Rotational Motion — Physics STD 11 Science — Question

Express 60°C in °F.

An artificial satellite revolving around the earth does not need any fuel. On the other hand, the aeroplane requires fuel to fly at a certain height.Why?

What is the effect on the direction of the centripetal force when the revolving body reverses its direction of motion?

Two astronauts on the surface of moon cannot talk to each other. Why?

Does the centre of mass of a solid necessarily lie within the body? If not, give an example.

What determines the natural frequency of a body?

Which of the following is the most precise device for measuring length: an optical instrument that can measure length to within a wavelength of light?

What does SONAR indicate?

Obtain the dimensions of relative density.

Solve the previous problem if the lead piece is fastened on the top surface of the block and the block is to float with its upper surface just dipping into water.