The blades of a windmill sweep out a circle of area A.
If the wind flows at a velocity V perpendicular to the circle, what is the mass of the air passing through it in time t?

The blades of a windmill sweep out a circle of area A.If the wind flows at a velocity V perpendicular to the circle, what is the Kinetic energy of the air passing through it in time t?

The blades of a windmill sweep out a circle of area A. Assume that the windmill converts 25% of the wind energy into electrical energy and that A=30 m^2 , v=36 km/h and density of air is 1.2kg//m^3 . What is the electrical power produced?

Prove that the tangent to the circle at any point on it is perpendicular to the radius passes through the point of contact.

The tangent to a circle and the radius passing through the point of contact are perpendicular to each other.

The mass of air striking the blades of a windmill every second is 400 kg . The velocity of the wind is 20 m*s^-1 . What is the rate of storage of energy in the windmill (in kW unit)? How much water can be raised per second , up to a height of 5m, using the windmill? g=10 m*s^(-2) .

The area of the circle which passes through the point (4,6) and whose centre is (1,2) is-

A particle of mass 'm' and carrying a charge q enters with a velocity 'v' perpendicular to a uniform magnetic field. The time period of rotation of the particle