Find the angular size of a circular object with a 3-inch diameter viewed from a distance of 9 yards.

**Solution:-**

The formula for angular size is shown below.

Angular size = physical size *

Note that the physical size of the object (its diameter) is given inches, while the viewing distance is given in yards. Convert the viewing distance to inches.

1 yard = 36 inches

8 yards = 288 inches

Substitute into the formula.

Angular size = (3 in)*

Perform the calculations.

angular size =

=

=