**Problem 6.4 Projection of Solids – **A sphere P, radius 20 mm; is resting on H.P. Another sphere Q, radius 15 mm is nailed to the sphere P. Line joining the centres of sphere P and sphere Q is parallel to V.P. and inclined to H.P. by 40^{0}. Draw the projection of the sphere and show the contact point in all views.

**Procedure: **

**Procedure:**

* Step-1* Draw a horizontal x-y line of some suitable length.

* Step-2* Draw a circle of diameter 20 mm, on the x-y line, as shown into the figure. And give the notations.

* Step-3* From the center of this circle, draw a center line which should be inclined at an angle 40° with the horizontal center line of the circle. On this center line mark a point at the distance 7.5 mm from the circumference of the circle, as shown into the figure. From this point draw a circle of radius equal to 7.5 mm, and give the notations. It is front view.

* Step-4* From the centers of the previously drawn circles of radii equal to 10 mm & 7.5 mm respectively, draw two vertical downward projectors up to some suitable distance below the x-y line, as shown into the figure. On these two projectors draw a horizontal center line parallel to x-y line at some suitable distance, and mark two points on them.

* Step-5* With these two points as center points, draw two circles of radii 10 mm & 7.5 mm respectively, and give the notations as shown into the figure. It is the top view.

* Step-6* Now draw x’-y’ line perpendicular with x-y line and on the right of front view, as shown into the figure. Now transfer the centers of the previously drawn circles on the right side of x’-y’ line as shown into the figure, and give the notations.

* Step-7* After getting the center points, draw two circles of radii equal to 10 mm & 7.5 mm respectively as shown into the figure. It is the Left Hand Side View.

* Step-8* Give the dimensions by any one method of dimensions and give the notations as shown into the figure.