At what distance does a man, whose height is 2 metres, subtend an angle of 10’ ?

The distance of the moon from the centre of the earth is 385,000 kilometres and moon’s diameter subtends an angle of 31’ at the eye of the observer. Find the diameter of the moon.

Assuming that a person of normal sight can read print to such distance that the letters subtend and angle of 5 at his eye, find the height of the letters that he can read at a distance of 12 metres.

Assuming that the earth’s radius is 6400 km and that it subtends an angle of 57’ at the centre of the moon, find the distance of the centre of the moon from the earth’s centre.

The radius of a circle whose arc of length 20pi subtends an angle of (2pi)/3 radians at the centre is:

Prove that the normal chord to a parabola at the point whose ordinate is equal to the abscissa subtends a right angle at the focus.

A water jet from the fountain reaches its maximum height of 4 metres at a distance of 0.5 metre from the vertical passing through the point A of the water outlet. Show that the height of the jet above the horizontal AX at a distance of 0.75 metre from the point A is 3 metres.

In the circle of 5cm.radius, what is the length of the arc which subtends and angle of 33^(@)15' at the centre.

Two parallel chords are drawn on the same side of the centre of a circle of radius R. It is found that they subtend and angle of theta and 2theta at the centre of the circle. The perpendicular distance between the chords is

A telescope has an objective lens of focal length 200 cm and an eye piece with focal length 2 cm.If this teleescope is used to see a 50 metre tall building at a distance of 2 km,what is the height of the image of the building formed by the objective lens?