Applied Mechanics and Graphic Statics MCQs

Question 1

The following statement is one of the laws of Dynamic friction

Accepted Answer

All the above

Answer

The force of friction always acts in a direction opposite to that in which a body is moving

Answer

The magnitude of the kinetic friction bears a constant ratio to the normal reaction between two surfaces. The ratio being slightly less than that in the case of limiting friction

Answer

For moderate speeds the force of friction remains constant but decreases slightly with the increase of speed

Question 2

If $$l$$ is the span of a light suspension bridge who's each cable carries total weight (w) and the central dip is y, the horizontal pull at each support, is

Accepted Answer

$$\frac{{{	ext{w}}l}}{{8{	ext{y}}}}$$

Answer

$$\frac{{{	ext{w}}l}}{{4{	ext{y}}}}$$

Answer

$$\frac{{{	ext{w}}l}}{{2{	ext{y}}}}$$

Answer

$${	ext{w}}l$$

Question 3

A 49 kg lady stands on a spring scale in an elevator. During the first 5 sec, starting from rest, the scale reads 69 kg. The velocity of the elevator will be

Accepted Answer

20 m/sec

Answer

10 m/sec

Answer

15 m/sec

Answer

25 m/sec

Question 4

Minimum pull in a suspended cable with supports at two ends is equal to

Accepted Answer

Horizontal thrust

Answer

Support reactions

Answer

Resultant of horizontal thrust and support reaction

Answer

Half the weight of the cable

Question 5

Pick up the correct statement from the following. The kinetic energy of a body

Accepted Answer

Before impact is more than that after impact

Answer

Before impact is equal to that after impact

Answer

Before impact is less than that after impact

Answer

Remain constant

Question 6

The force polygon representing a set of forces in equilibrium is a

Accepted Answer

Closed polygon

Answer

Triangle

Answer

Open polygon

Answer

Parallelogram

Question 7

A system of coplanar forces is in equilibrium when

Accepted Answer

Both force polygon" and funicular polygon close

Answer

Force polygon closes

Answer

Funicular polygon closes

Answer

All the forces are concurrent

Question 8

In which of the following trusses, the method of substitution is required for determining the forces in all the members of the truss by graphic statics?

Accepted Answer

Fink truss

Answer

Howe truss

Answer

King post truss

Answer

Warren truss

Question 9

One end of a light string 4 m in length is fixed to a point on a smooth wall and the other end fastened to a point on the surface of a smooth sphere of diameter 2.25 m and of weight 100 kg. The tension in the string is

Accepted Answer

22.5 kg

Answer

17.5 kg

Answer

19.5 kg

Answer

25 kg