Q-3(a). The sketch in fig. 3 shows M and N, 50 apart. Point P moves such that its distance from M and N is always in the ratio of 2:1.
Plot the locus of P for one complete revolution.
Procedure:
1. To plot the locus of a point P which moves so that its distance from two fixed points M and N. 50 mm apart, is always in the ratio 2:1 respectively (Fig 3)
2. The first point to plot is the one that lies between M and N - Since It is twice as far away from M as it is from N. This is done by proportional division of the line.
3. If we now let P be 40 mm from M it must be 20 mm from N. Thus, the second position of P is at the intersection of an arcs; with centre M, radius 40 mm and another arc with centre N and radius 20 mm.
4. The third position of P is the intersection of arcs, radii 50 mm and 25 mm; centres M and N respectively.
5. This is continued for as long as necessary. In this case, at a point 100 mm from M and 50 mm from N, the locus meets itself to form a circle.
6. Use the table in the video to generate fig. 3a in the PDF worksheet below 👇
Download alternative 2 PDF version here - drive.google.com/file/d/1yuhh...