# Engineering Drawing Questions and Answers – Construction of Parallel & Perpendicular Lines – 1

«
»

This set of Engineering Drawing Multiple Choice Questions & Answers (MCQs) focuses on “Construction of Parallel & Perpendicular Lines – 1”.

1. Given are the steps to draw a perpendicular to a line at a point within the line when the point is near the centre of a line.
Arrange the steps. Let AB be the line and P be the point in it
i. P as centre, take convenient radius R1 and draw arcs on the two sides of P on the line at C, D.
ii. Join E and P
iii. The line EP is perpendicular to AB
iv. Then from C, D as centre, take R2 radius (greater than R1), draw arcs which cut at E.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, i, iv, iii

Explanation: Here uses the concept of a locus. Every 2 points have a particular line that is every point on line is equidistant from both the points. The above procedure shows how the line is build up using arcs of the similar radius.

2. Given are the steps to draw a perpendicular to a line at a point within the line when the point is near an end of the line.
Arrange the steps. Let AB be the line and P be the point in it.
i. Join the D and P.
ii. With any point O draw an arc (more than a semicircle) with a radius of OP, cuts AB at C.
iii. Join the C and O and extend till it cuts the large arc at D.
iv. DP gives the perpendicular to AB.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, iii, i, iv

Explanation: There exists a common procedure for obtaining perpendiculars for lines. But changes are due changes in conditions whether the point lies on the line, off the line, near the centre or near the ends etc.

3. Given are the steps to draw a perpendicular to a line at a point within the line when the point is near the centre of line.
Arrange the steps. Let AB be the line and P be the point in it
i. Join F and P which is perpendicular to AB.
ii. Now C as centre take the same radius and cut the arc at D and again D as centre with same radius cut the arc further at E.
iii. With centre as P take any radius and draw an arc (more than a semicircle) cuts AB at C.
iv. Now D, E as centre take radius (more than half of DE) draw arcs which cut at F.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, i, iv, iii

Explanation: Generally in drawing perpendiculars to lines involves in drawing a line which gives equidistance from either side of the line to the base, which is called the locus of points. But here since the point P is nearer to end, there exists some peculiar steps in drawing arcs.

4. Given are the steps to draw a perpendicular to a line from a point outside the line, when the point is near the centre of line.
Arrange the steps. Let AB be the line and P be the point outside the line
i. The line EP is perpendicular to AB
ii. From P take convenient radius and draw arcs which cut AB at two places, say C, D.
iii. Join E and P.
iv. Now from centers C, D draw arc with radius (more than half of CD), which cut each other at E.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, iv, iii, i

Explanation: At first two points are taken from the line to which perpendicular is to draw with respect to P. Then from two points equidistant arcs are drawn to meet at some point which is always on the perpendicular. So by joining that point and P gives perpendicular.

5. Given are the steps to draw a perpendicular to a line from a point outside the line, when the point is near an end of the line.
Arrange the steps. Let AB be the line and P be the point outside the line
i. The line ED is perpendicular to AB
ii. Now take C as centre and CP as radius cut the previous arc at two points say D, E.
iii. Join E and D.
iv. Take A as center and radius AP draw an arc (semicircle), which cuts AB or extended AB at C.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, ii, i, iii
d) ii, iv, iii, i

Explanation: The steps here show how to draw a perpendicular to a line from a point when the point is nearer to end of line. Easily by drawing arcs which are equidistance from either sides of line and coinciding with point P perpendicular has drawn.

6. Given are the steps to draw a perpendicular to a line from a point outside the line, when the point is nearer the centre of line.
Arrange the steps. Let AB be the line and P be the point outside the line
i. Take P as centre and take some convenient radius draw arcs which cut AB at C, D.
ii. Join E, F and extend it, which is perpendicular to AB.
iii. From C, D with radius R1 (more than half of CD), draw arcs which cut each other at E.
iv. Again from C, D with radius R2 (more than R1), draw arcs which cut each other at F.
a) i, iii, iv, ii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, iv, iii, i

Explanation: For every two points there exists a line which has points from which both the points are equidistant otherwise called perpendicular to line joining the two points. Here at 1st step, we created two on the line we needed perpendicular, then with equal arcs from either sides we created the perpendicular.

7. Given are the steps to draw a parallel line to given line AB at given point P.
Arrange the steps.
i. Take P as centre draw a semicircle which cuts AB at C with convenient radius.
ii. From C with radius of PD draw an arc with cuts the semicircle at E.
iii. Join E and P which gives parallel line to AB.
iv. From C with same radius cut the AB at D.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, iv, iii, i

Explanation: There exists some typical steps in obtaining parallel lines for required lines at given points which involves drawing of arcs, necessarily, here to form a parallelogram since the opposite sides in parallelogram are parallel.

8. Given are the steps to draw a parallel line to given line AB at a distance R.
Arrange the steps.
i. EF is the required parallel line.
ii. From C, D with radius R, draw arcs on the same side of AB.
iii. Take two points say C, D on AB as far as possible.
iv. Draw a line EF which touches both the arc (tangents) at E, F.
a) i, iv, ii, iii
b) iii, ii, iv, i
c) iv, iii, i, ii
d) ii, iv, iii, i

Explanation: Since there is no reference point P to draw parallel line, but given the distance, we can just take arcs with distance given from the base line and draw tangent which touches both arcs.

9. Perpendiculars can’t be drawn using _____________
a) T- Square
b) Set-squares
c) Pro- circle
d) Protractor

Explanation: T-square is meant for drawing a straight line and also perpendiculars. And also using set-squares we can draw perpendiculars. Protractor is used to measure angles and also we can use to draw perpendiculars. But pro-circle consists of circles of different diameters.

10. The length through perpendicular gives the shortest length from a point to the line.
a) True
b) False

Explanation: The statement given here is right. If we need the shortest distance from a point to the line, then drawing perpendicular along the point to a line is the best method. Since the perpendicular is the line which has points equidistant from points either side of given line.

Sanfoundry Global Education & Learning Series – Engineering Drawing.

To practice all areas of Engineering Drawing, here is complete set of 1000+ Multiple Choice Questions and Answers. 