1 ) The accuracy of the solution to a problem depends upon two items : -
(1) the accuracy
of the given data and
(2) the accuracy of the computations performed . Single choice.
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
2 ) Most of the
bodies considered in elementary mechanics are assumed to be rigid . We define a rigid body as one that does not
deform .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
3 ) Two important
concepts associated with the effect of a force on a rigid body are the moment
of a force about a point and the moment of a force about an axis .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
4 ) we can replace
any system of forces acting on a rigid body by an equivalent system consisting
of one force acting at a given point and one couple . This basic combination is called a force -
couple system .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
5 ) Forces acting
on rigid bodies can be separated into two groups : -
(1) external forces and
(2) internal forces .
A ) True ,
B ) False ,
Correct answers : - A
) True
,
6 ) External
forces are exerted by other bodies on the rigid body under consideration .
A ) True ,
B ) False ,
Correct answers : - A ) True
,
7 ) Internal forces hold together the particles
forming the rigid body .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
8 ) Mixed Triple
Product of Three Vectors S P and Q can
be written as : -
A ) S . (P X Q)
,
B ) S x (P . Q) ,
C ) S x (P x Q) ,
D ) S . (P . Q) ,
Correct answers : -
A ) S . (P X Q)
,
9 ) Scalar Product
of Two Vectors : -
A ) P . Q = PQ
cos θ ,
B ) P . Q = PQ sin θ ,
C ) P x Q = PQ
sin θ ,
D ) P x Q = PQ
sin θ ,
Correct answers : -
A ) P
. Q = PQ cos θ ,
10 ) Parallel
forces have parallel lines of action and may or may not have the same sense( direction
) .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
11 ) Coplanar
forces act in the same plane .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
12 ) Concurrent
forces act at the same point .
A ) True ,
B ) False ,
Correct answers : - A ) True ,
13 ) Any force F
acting on a rigid body can be moved to an arbitrary point O provided that we
add a couple whose moment is equal to the moment of F about O .
A ) True ,
B ) False ,
Correct answers : - A ) True
,
14 ) We can reduce
any system of forces, no matter how complex they are , to an equivalent
force-couple system acting at a given point O .
A ) True ,
B ) False ,
Correct answers : -
A ) True ,
15 ) Two systems
of forces are equivalent if they can be reduced to the same force - couple
system at a given point O .
A ) True ,
B ) False ,
Correct answers : - A ) True ,
16 ) Two systems of forces are equivalent if they tend to
impart to the rigid body (1) the same translation in the x , y , and z
directions , respectively , and (2) the same rotation about the x , y , and z
axes , respectively .
A ) True ,
B ) False ,
Correct answers : - A ) True
,
17 ) In general ,
when two systems of vectors satisfy such that when their force resultants and
their moment resultants about an arbitrary point O are respectively equal , the
two systems are said to be equipollent .
A ) True ,
B ) False ,
Correct answers : - A ) True ,
18 ) If two systems of forces acting on a rigid body are
equipollent , they are also equivalent .
A ) True ,
B ) False ,
Correct answers : - A ) True ,
19 ) Moment of a
Force about an Axis line OL is given as …………….. ,
A ) M(OL) = λ . M(O) ,
B ) M(OL) = λ x
M(O) ,
Correct answers : - A ) M(OL)
= λ . M(O) ,
20 ) Projection of a Vector on an Axis OL is given as …………..
,
A ) P(OL) = P.
λ(OL) ,
B ) P(OL) = P x
λ(OL) ,
Correct answers : -
A ) P(OL) = P. λ(OL) ,
21 ) Forces are
called concurrent when their lines of action meet in …………. ,
A ) plane ,
B ) two points ,
C ) one point ,
Correct answers : - C ) one
point ,
22 ) Forces are
called coplanar when all of them acting on body lie in ……….. ,
A ) one point ,
B ) one plane ,
C ) different
planes ,
Correct answers : -
B ) one plane ,
23 ) Effect of a
force on a body depends upon …………… ,
A ) all of the
above ,
B ) direction ,
C ) position or
line of action ,
D ) magnitude ,
Correct answers : - A ) all
of the above ,
24 ) When trying to turn a key into a lock , the
following is applied .
A ) coplanar force
,
B ) couple ,
C ) lever ,
Correct answers : -
B ) couple ,
25 ) According to
the principle of transmissibility of forces , the effect of a force upon a body
is ……………… ,
A ) maximum when
it acts at the centre of gravity of a body ,
B ) the same at
every point in its line of action ,
C ) different at
different points in its line of action ,
Correct answers : -
B ) the same at every point in its line of action
,
26 ) Which of the
following is a vector quantity ?
A ) Moment about a
point ,
B ) Energy of
system ,
C ) Moment about a
line ,
Correct answers : - A ) Moment
about a point ,
27 ) A number of
forces acting at a point will be in equilibrium if …………………. ,
A ) sum of
resolved components is zero ,
B ) their total
sum is non zero ,
C ) moment of
forces is non zero ,
Correct answers : -
A ) sum of resolved components is zero ,
28 ) According to
the principle of moments ……. ,
A ) the algebraic
sum of the moments of any two forces about any point is equal to moment of
their resultant about the same point ,
B ) if a system of
coplanar forces is in equilibrium , then the algebraic sum of their moments
about any point in their plane is zero .
C ) if a system of
coplanar forces is in equilibrium , then their algebraic sum is zero .
Correct answers :
- B ) if
a system of coplanar forces is in equilibrium , then the algebraic sum of their
moments about any point in their plane is zero .
29 ) According to the law of triangle of forces ……. ,
A ) the lines of
action of these forces meet in a point ,
B ) if three
forces acting at a point they will be in equilibrium ,
C ) if three
forces acting upon a particle are represented in magnitude and direction by the
sides of a triangle , taken in order , they will be in equilibrium .
Correct answers : -
C ) if three forces acting upon a particle are
represented in magnitude and direction by the sides of a triangle , taken in
order , they will be in equilibrium .
30 ) Which of the following
is a vector quantity ?
A ) Force ,
B ) Energy ,
C ) Mass ,
Correct answers : -
A ) Force ,
