Diameter form of the circle

N is the foot of the perpendicular form P to the diameter AB of the circle APB. P lies on the circle APB. Prove that PB^2=AB.NB ,

Two equal circles are drawn in square in such a way that a side of the square forms diameter of each circle. If the remaining area of the square is 42 cm2. How much will the diameter of the circle measures? (a) 3.5 cm (b) 4 cm (c) 14 cm (d) 7.5 cm

In the picture a triangle is formed by two mutually perpendicular tangents to a circle and a third tangent. Prove that the perimeter of the triangle is equal to the diameter of the circle.

A chord 16 cm long is 6 cm distant form the centre of the circle . Find the diameter of the circle.

A wire of resistance 5 Omega is bent in the form of a closed circle. Find the resistance across the diameter of the circle.

A chord 16 cm long is 6 cm distant form the centre of the circle . Find the diameter of the circle.