Technical Drawing 2, Nov/Dec 2015

Question 2

 

 

(2)        A cylindrical bar, 50 diameter, rolls up a ramp having a slope of 300 to the horizontal without slipping as shown above.
(a)        Construct the path of the point P on the rim of the bar as it makes one complete revolution up the ramp.
(b)        Name the curve obtained.

Observation

Most of the candidates attempted this question and performed very well.  The solution required indentifying different positions of the point on the circles as it rolls up the ramp.
Candidates were expected to do the following:

CYCLOID

(a)        (i)        draw slanting base at 300 to the  horizontal;
(ii)         draw circle (1) and divide into 12 equal points;
(ii)         lay out the circumference of the circle;
(iv)        erect perpendiculars from divisional points on the circumference;
(v)        project lines parallel to the base AB from divisions on circle.

 

The solution is shown below: