Multiple choice question for engineering
Set 1
1. How is tapped hole of diameter 10mm with 20mm dimensioned?
a) M10
b) M10, 20
c) M10, DEEP 20
d) M10 20 mm deep
Answer
Answer: c [Reason:] A tapped hole of 10mm diameter and 20mm deep is dimensioned as M10, DEEP 20. The ‘M’ stands for metric threads. These are standard threads whose pitch is predefined according to the diameter. The ‘M’ indicates that the hole is tapped.
2. How is a blind drilled hole of 15mm diameter and 15mm deep dimensioned?
a) M15, DEEP 15
b) φ15, DEEP 15
c) φ15
d) φ15 x 15
Answer
Answer: b [Reason:] Since the hole is not through, it is mandatory to mention the depth of the hole while dimensioning. Hence a blind drilled hole of 15mm diameter and 15mm deep is dimensioned as φ15, DEEP 15. Since the hole is not threaded ‘M’ should not be used for dimensioning.
3. The dimensions of circular part or arc should be given where the true shape is visible.
a) True
b) False
Answer
Answer: a [Reason:] Circular parts and arcs should be dimensioned where their true shapes are visible. Proper notations should be used to dimension circles and arcs. This will help in clarifying the dimension and reduces the confusion if there are any.
4. A chamfer of 3mm thick and angle 45˚ inclination is dimensioned as _____
a) 45˚ x 3
b) 3 x 45˚
c) 45˚
d) 3mm
Answer
Answer: b [Reason:] A chamfer of 3mm thickness and angle 45˚ is dimensioned as 3 x 45˚. From this dimension, we can get the information of the angle at which the chamfer is cut and the distance from one of the sides. This helps in reading of the dimensions easy.
5. The leader should be used to dimension the circle.
a) True
b) False
Answer
Answer: a [Reason:] The leader lines should be used to dimension the circle. This helps in identifying the true shape as well the dimension related to the circle. It is advised not to dimension cylinders in the views where it is seen as any shape other than circle but should be dimensioned where its cross-section is clearly visible.
6. What does dimensioning of a circle depend upon?
a) Shape
b) Length
c) Unit
d) Size
Answer
Answer: d [Reason:] The dimensioning of the circle depends upon the size or diameter of the circle. If the diameter of the circle is considerably large, the dimension can be given inside the circle itself. It should be noted that the dimension of the circle should be given in the view where its true shape is visible.
7. The dimensions which are smaller are to be placed _______
a) Nearer to the view
b) Further from the outline of the view
c) Inside the view
d) On the view
Answer
Answer: a [Reason:] The dimensions which are smaller should be placed nearer to the view while the larger view should be place further away. Dimensions large or small should not be placed on the view. Extension lines should be used and the outlines of ht view for dimensioning.
8. While dimensioning, where should the large dimensions be placed?
a) On the outlines of the view
b) Near the view
c) Further away from the view
d) Inside the view
Answer
Answer: c [Reason:] The larger dimensions should be placed further away from the outlines of the view. They should be placed beyond the smaller dimensions. This helps in a neat arrangement of the dimensions and can be understood easily.
9. Extension lines should start from which part of the drawing?
a) Away from the outlines
b) From inside the views
c) No need for extension lines
d) Outlines of the view
Answer
Answer: d [Reason:] Extension lines should start immediately from the outlines of the views. There should be no gap between the outlines and the extension lines. Dimensions should not be given on the outlines themselves and therefore extension lines should be used.
10. Dimensions can be placed anywhere irrespective of the features visible.
a) True
b) False
Answer
Answer: b [Reason:] Dimensions have to be placed where the true shape or features are clearly indicated. For example, if there is cylindrical hole in the object, the size of the cylinder i.e. the diameter of the base circle should be dimensioned in the view where it is seen as circle and not in the view where the cylinder is seen as rectangle.
Set 2
1. The advised position of placement of the dimensions should be ______
a) Inside the view
b) Outside the view
c) On the boundaries of the view
d) Cutting the view
Answer
Answer: b [Reason:] It is advised to place the dimensions outside the view. This will bring clear picture of the view and will help in the understanding of the dimensions. Placing the dimensions outside the view gives a cleaner look.
2. From the following figure, which is the repetitive dimension?
a) 30
b) 70
c) 10
d) 20
Answer
Answer: c [Reason:] From the front view it is clear that the circle has diameter 20 mm. Hence its radius will be 10mm. The dimension 10mm in the side view is just a repetition of this information. Repetitive dimensions are redundant and they need to be avoided.
3. Which of the following dimensions is arranged haphazardly?
a) 45 in S.V.
b) 45 in F.V.
c) 30 in S.V.
d) 30 in F.V.
Answer
Answer: d [Reason:] The dimension 30mm is repeated and is placed in a haphazard manner. There is no need for the dimension in F.V. as it is clearly understood from the S.V. Such dimensions should be avoided at all costs.
4. If there is a need for the center line, then it can be used as a _____
a) Dimension line
b) Leader line
c) Extension line
d) Section line
Answer
Answer: c [Reason:] The center line can be used an extension line. With the help of the center line as extension line, we can dimension the distance between the centers of the circles from the outline view of the object. Thus helps in drawing the circle accurately.
5. Which of the following dimension is incorrect?
a) 22.5
b) 15
c) 20
d) 35
Answer
Answer: c [Reason:] The dimension 20mm is given without using the extension line. The outline of the view is used to dimension the line. This is not usually favoured. Always use extension line and place the dimension line in between the extension lines.
6. Dimension lines should not intersect each other as far as possible.
a) True
b) False
Answer
Answer: a [Reason:] Dimension should never intersect each other as far possible. Intersecting dimension lines can cause confusion and needs more effort to understand them. To increase the readability of the dimension they should not intersect with each other.
7. Different units of measurement can be used in dimensioning a view.
a) True
b) False
Answer
Answer: b [Reason:] All dimensions should be expressed in one unit. Using different units for dimensions will create confusion for the observer and there is a chance of misinterpretation. Therefore, using different units should be avoided and a tag ‘All dimensions are in mm’ should be added above the title page.
8. While dimensioning a cylinder in the view where the true shape of the cylinder is not visible, which symbol is used to denote that it is a cylinder?
a) •
b) φ
c) ϴ
d) ○
Answer
Answer: b [Reason:] Since the true shape of the cylinder is circle from one view, we used the symbol φ followed by the dimension figure while dimensioning it in the view where it is seen as a rectangle. The cross-section of the rectangle is square then the symbol • followed by the dimension figure is used.
9. As far as possible, dimension should be given to which of the following lines?
a) Outline
b) Hidden line
c) Center line
d) Leader line
Answer
Answer: a [Reason:] Dimensions are given to the outlines of the view. It is advised not to dimension hidden lines as their true shape is not known when they hidden. It is important to dimension those lines whose true shape is properly visible.
10. How is a spot face hole with 24mm diameter, 5mm deep and spot face diameter 10mm dimensioned?
a) Φ24 and φ10
b) 5 SPOT FACE, φ24 X φ10
c) φ24 SPOT FACE, φ10
d) φ10 SPOT FACE, φ24 x 5 DEEP
Answer
Answer: d [Reason:] Holes made by spot facing are dimensioned in this manner ‘φ10 SPOT FACE, φ24 x 5 DEEP’. This means the there is a spot face of 10mm diameter after the 24mm diameter and 5 mm thickness. Using this makes the reading of the dimension easy.
Set 3
1. The sections cut by a plane on a right circular cone are called as ______
a) Parabolic sections
b) Conic sections
c) Elliptical sections
d) Hyperbolic sections
Answer
Answer: b [Reason:] The sections cut by a plane on a right circular cone are called as conic sections or conics. The plane cuts the cone on different angles with respect to the axis of the cone to produce different conic sections.
2. Which of the following is a conic section?
a) Circle
b) Rectangle
c) Triangle
d) Square
Answer
Answer: a [Reason:] Circle is a conic section. When the plane cuts the right circular cone at right angles with the axis of the cone, the shape obtained is called as circle. If the angle is oblique we get the other parts of the conic sections.
3. In conics, the _____ is revolving to form two anti-parallel cones joined at the apex.
a) Ellipse
b) Circle
c) Generator
d) Parabola
Answer
Answer: c [Reason:] In conics, the generator is revolving to form two anti-parallel cones joined at the apex. The plane is then made to cut these cones and we get different conic sections. If we cut at right angles with respect to the axis of the cone we get a circle.
4. While cutting, if the plane is at an angle and it cuts all the generators, then the conic formed is called as ______
a) Circle
b) Ellipse
c) Parabola
d) Hyperbola
Answer
Answer: b [Reason:] If the plane cuts all the generators and is at an angle to the axis of the cone, then the resulting conic section is called as ellipse. If the cutting angle was right angle and the plane cuts all the generators then the conic formed would be circle.
5. If the plane cuts at an angle to the axis but does not cut all the generators then what is the name of the conics formed?
a) Ellipse
b) Hyperbola
c) Circle
d) Parabola
Answer
Answer: d [Reason:] If the plane cuts at an angle with respect to the axis and does not cut all the generators then the conics formed is a parabola. If the plane cuts all the generators then the conic section formed is called as ellipse.
6. When the plane cuts the cone at angle parallel to the axis of the cone, then _____ is formed.
a) Hyperbola
b) Parabola
c) Circle
d) Ellipse
Answer
Answer: a [Reason:] When the plane cuts the cone at an angle parallel to the axis of the cone, then the resulting conic section is called as hyperbola. If the plane cuts the cone at an angle with respect to axis of the cone then the resulting conic sections are called as ellipse and parabola.
7. Which of the following is not a conic section?
a) Apex
b) Hyperbola
c) Ellipse
d) Parabola
Answer
Answer: a [Reason:] Conic sections are formed when a plane cuts through the cone at an angle with respect to the axis of the cone. If the angle is right angle then the conics is circle, if the angle is oblique then the resulting conics are parabola and ellipse.
8. The locus of point moving in a plane such that the distance between a fixed point and a fixed straight line is constant is called as ________
a) Conic
b) Rectangle
c) Square
d) Polygon
Answer
Answer: a [Reason:] The locus of a point moving in a plane such that the distance between a fixed point and a fixed straight line is always constant. The fixed straight line is called as directrix and the fixed point is called as focus.
9. The ratio of the distance from the focus to the distance from the directrix is called as eccentricity.
a) True
b) False
Answer
Answer: a [Reason:] The ratio of the distance from the focus to the distance from the directrix is called as eccentricity. It is denoted as e. The value of eccentricity can give information regarding which type of conics it is.
10. Which of the following conics has an eccentricity of unity?
a) Circle
b) Parabola
c) Hyperbola
d) Ellipse
Answer
Answer: b [Reason:] Eccentricity is defined as the ratio of the distance from the focus to the distance from the directrix. It is denoted as e. The value of eccentricity can give information regarding which type of conics it is. The eccentricity of parabola is unity that is 1.
11. Which of the following has an eccentricity less than one?
a) Circle
b) Parabola
c) Hyperbola
d) Ellipse
Answer
Answer: d [Reason:] Eccentricity is defined as the ratio of the distance from the focus to the distance from the directrix. It is denoted as e. The value of eccentricity can give information regarding which type of conics it is. The eccentricity of ellipse is less than one.
12. If the distance from the focus is 10 units and the distance from the directrix is 30 units, then what is the eccentricity?
a) 0.3333
b) 0.8333
c) 1.6667
d) 0.0333
Answer
Answer: a [Reason:] Eccentricity is defined as the ratio of the distance from the focus to the distance from the directrix. Hence from the formula of eccentricity, e = 10 ÷ 30 = 0.3333. Since the value of eccentricity is less than one the conic is ellipse.
13. If the value of eccentricity is 12, then what is the name of the conic?
a) Ellipse
b) Hyperbola
c) Parabola
d) Circle
Answer
Answer: b [Reason:] Eccentricity is defined as the ration of the distance from the focus to the distance from the directrix. It is denoted as e. If the value of eccentricity is greater than unity then the conic section is called as hyperbola.
14. If the distance from the focus is 3 units and the distance from the directrix is 3 units, then how much is the eccentricity?
a) Infinity
b) Zero
c) Unity
d) Less than one
Answer
Answer: c [Reason:] Eccentricity is defined as the ration of the distance from the focus to the distance from the directrix and it is denoted as e. Hence from the definition, e = 3 ÷ 3 = 1. Hence the value of eccentricity is equal to unity.
15. If the distance from the focus is 2 mm and the distance from the directrix is 0.5 mm then what is the name of the conic section?
a) Circle
b) Ellipse
c) Parabola
d) Hyperbola
Answer
Answer: d [Reason:] The eccentricity is defined as the ratio of the distance from the focus to the distance from the directrix. It is denoted as e. If the value of the eccentricity is greater than unity then the conic section is called as hyperbola.
Set 4
1. The straight lines which are drawn from various points on the contour of an object to meet a plane are called as _________
a) connecting lines
b) projectors
c) perpendicular lines
d) hidden lines.
Answer
Answer: b [Reason:] The object will generally kept at a distance from planes so to represent the shape in that view projectors are drawn perpendicular to plane in orthographic projection. Projectors are simply called lines of sights when an observer looks towards an object from infinity.
2. When the projectors are parallel to each other and also perpendicular to the plane, the projection is called ___________________________
a) Perspective projection
b) Oblique projection
c) Isometric projection
d) Orthographic projection
Answer
Answer: d [Reason:] In orthographic projection the projectors are parallel to each other and also perpendicular to the plane but in oblique projection the projectors are inclined to the plane of projection and projectors are parallel to each other.
3. In the Oblique projection an object is represented by how many views?
a) one view
b) two views
c) three views
d) four views
Answer
Answer: a [Reason:] Oblique projection is one method of pictorial projection. Oblique projection shows three dimensional objects on the projection plane in one view only. This type of drawing is useful for making an assembly of an object and provides directly a production drawing.
4. The object we see in our surrounding usually without drawing came under which projection?
a) Perspective projection
b) Oblique projection
c) Isometric projection
d) Orthographic projection
Answer
Answer: a [Reason:] Perspective projection gives the view of an object on a plane surface, called the picture plane, as it would appear to the eye, when viewed from a fixed position. It may also be defined as the figure formed on the projection plane when visual rays from the eye to the object cut the plane.
5. In orthographic projection each projection view represents how many dimensions of an object?
a) 1
b) 2
c) 3
d) 0
Answer
Answer: b [Reason:] In orthographic projection and oblique projection the projection planes which represent one view of an object only shows width, height; width, thickness; height, thickness only but in isometric and perspective projections width, height and thickness can also be viewed.
6. In orthographic projection an object is represented by two or three views on different planes which _________________
a) gives views from different angles from different directions
b) are mutually perpendicular projection planes
c) are parallel along one direction but at different cross-section
d) are obtained by taking prints from 2 or 3 sides of object
Answer
Answer: b [Reason:] By viewing in mutual perpendicular planes- Vertical plane, horizontal plane, profile plane which indirectly gives us front view in x-direction, top-view in y –direction and thickness in z-direction which are mutually perpendicular. Ortho means perpendicular.
7. To represent the object on paper by orthographic projection the horizontal plane (H.P) should be placed in which way?
a) The H.P is turned in clockwise direction up to 90 degrees
b) The H.P is turned in anti-clockwise direction up to 90 degrees
c) H.P plane is placed to left side of vertical plane parallel to it
d) H.P plane is placed to right side of vertical plane parallel to it
Answer
Answer: a [Reason:] The vertical plane and horizontal plane are perpendicular planes intersected at reference line. So on paper to represent perpendicular planes any of the planes should arrange to get real picture of required projection.
8. The hidden parts inside or back side of object while represented in orthographic projection are represented by which line?
a) Continuous thick line
b) Continuous thin line
c) Dashed thin line
d) Long-break line
Answer
Answer: c [Reason:] Continuous thick line is used for visible outlines, visible edges, crests of screw threads, limits of full depth thread etc. Continuous thin line is used for extension, projection, short centre, leader, reference lines, imaginary lines of intersection etc.
9. Orthographic projection is the representation of two or more views on the mutual perpendicular projection planes.
a) True
b) False
Answer
Answer: a [Reason:] Orthographic projection is the representation of two or more views on the mutual perpendicular projection planes. But for oblique projection the object is viewed in only one view. And in isometric view the object is kept resting on the ground on one of its corners with a solid diagonal perpendicular to the V.P.
10. In perspective projection and oblique projection the projectors are not parallel to each other.
a) True
b) False
Answer
Answer: b [Reason:] In Oblique projection the projectors are parallel to each other but inclined to projection plane but in perspective projection all the projectors are not parallel to each other and so to projection plane.
11. What is additional 3rd view on orthographic projection in general for simple objects?
a) Front view
b) Top view
c) Side view
d) View at 45 degrees perpendicular to horizontal plane
Answer
Answer: c [Reason:] In general for simple objects engineers use only front view and top view or else front view and side view or else top view and side view. If every view is visualized side view gives height and thickness of object.
12. The front view of an object is shown on which plane?
a) Profile plane
b) Vertical plane
c) Horizontal plane
d) Parallel plane
Answer
Answer: b [Reason:] The front view will be represented on vertical plane, top view will be represented on horizontal plane and side view will be shown on profile plane. The front view shows height and width of object.
13. The Top view of an object is shown on which plane?
a) Profile plane
b) Vertical plane
c) Horizontal plane
d) Parallel plane
Answer
Answer: c [Reason:] The front view will be shown on vertical plane, top view will be represents on horizontal plane and side view will be represents on profile plane. The top view gives thickness and width of the object.
14. The side view of an object is shown on which plane?
a) Profile plane
b) Vertical plane
c) Horizontal plane
d) Parallel plane
Answer
Answer: a [Reason:] The front view will be represents on vertical plane, top view will be shown on horizontal plane and side view will be represents on profile plane. The side view gives height and thickness of object.
Set 5
1. Oblique planes come under ________________
a) planes perpendicular to both reference planes
b) planes perpendicular to one reference plane and inclined to other reference plane
c) planes inclined to both the reference planes
d) planes parallel to one reference plane and perpendicular to other reference plane
Answer
Answer: c [Reason:] Planes may be divided into two main types. i. Perpendicular planes and ii. Oblique planes, planes which are held inclined to both the reference planes are called oblique planes, the rest come under perpendicular planes.
2. The planes which are perpendicular to both the reference plane (horizontal and vertical) are visible clearly only if we watched from ___________
a) front view
b) top view
c) side view
d) isometric view
Answer
Answer: c [Reason:] As the required plane is perpendicular to both horizontal plane and vertical plane the top view and front view gives a line in projections so only from side which is perpendicular to both the plane as the required plane the object will appear clearly isometric view also will not give vivid picture.
3. A plane is held parallel to horizontal plane in which view we can watch drawing on that plane?
a) Top view
b) Front view
c) Back view
d) Side view
Answer
Answer: a [Reason:] If a plane is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is parallel to horizontal plane the actual shape is watched from top view.
4. A circle is placed at 20 degrees with vertical the view from top view will be __________
a) line
b) circle
c) ellipse
d) oval
Answer
Answer: c [Reason:] If a circle is parallel to one of the reference plane the projection parallel to plane gives the true shape and size but here plane is inclined so circle transformed to ellipse. If observer also inclined along with plane the circle will remain circle only.
5. A square is held 30 degrees with horizontal plane and turned 30 degrees with respect to vertical plane keeping earlier condition constant. The top view will be ________________
a) line
b) square
c) rectangle
d) parallelogram
Answer
Answer: c [Reason:] If a square is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is inclined so square transformed to rectangle and further it turned parallel to observer so no change in shape and size.
6. A square is held 30 degrees with horizontal plane and turned 30 degrees with respect to vertical plane keeping earlier condition constant. The front view will be _____________
a) line
b) square
c) rectangle
d) parallelogram
Answer
Answer: d [Reason:] If a square is parallel to one of the reference plane the projection parallel to plane gives the true shape and size as here plane is inclined so square transformed to rectangle and further it turned inclined in other way which gives parallelogram shape for square.
7. A triangle is placed perpendicular to both the reference planes (horizontal and vertical plane) which of the following statement is true.
a) Front view-line, top view- triangle
b) Front view-triangle, top view- line
c) Front view –line, top view-line
d) Front view-triangle, side view- line
Answer
Answer: c [Reason:] The plane which is perpendicular to both the reference planes (horizontal and vertical plane) is called profile plane or picture plane. The planes parallel to these have top view and front view as straight line.
8. When a plane is perpendicular to both the reference planes, its traces are perpendicular to ______________
a) xy reference line
b) lines on horizontal plane
c) lines on vertical plane
d) lines on given plane
Answer
Answer: a [Reason:] When a plane is perpendicular to both the reference planes, its traces are perpendicular to xy reference line and intersect at xy reference line even when the planes are inclined with both reference planes the traces intersect at xy line.
9. A plane perpendicular to vertical plane and inclined to horizontal plane then the vertical trace of that plane will be _____________
a) parallel to horizontal plane
b) perpendicular to horizontal plane
c) parallel to xy reference line
d) inclined to horizontal plane
Answer
Answer: d [Reason:] When a plane is perpendicular to one of the reference planes and inclined to the other, its inclination is shown by the angle which its projection on the plane to which it is perpendicular, makes with xy. Its projection on the plane to which it is inclined, is smaller than the plane itself.
10. A plane parallel to vertical plane then which of the following is false statement.
a) vertical trace will not present
b) horizontal trace is parallel to xy
c) front view give true shape and size
d) top view give true shape and size
Answer
Answer: d [Reason:] When a plane is parallel to a reference plane, it has no trace on that plane. Its trace on the other reference plane, to which the earlier reference plane is perpendicular, is parallel to xy reference line.
11. When a plane is perpendicular to a reference plane, its projection on that plane shows its true shape and size.
a) True
b) False
Answer
Answer: b [Reason:] When a plane is perpendicular to a reference plane, its projection on that plane is a straight line. When a plane is parallel to a reference plane, its projection on that plane shows its true shape and size.
12. The traces of plane are not intersecting at xy reference line then the plane is __________
a) inclined to H.P and perpendicular to V.P
b) parallel to H.P and perpendicular to V.P
c) perpendicular to both reference planes
d) inclined to V.P and perpendicular to H.P
Answer
Answer: b [Reason:] When a plane has two traces, they, produced if necessary, intersect in xy except when both are parallel to xy reference line as in case of some oblique planes. And in those some specific are plane parallel to one reference and perpendicular to other.