MCQ
1621. When trying to turn a key into a lock, following is applied-
coplanar force
non-coplanar forces
lever
couple
1622. The co-efficient of friction depends upon-
nature of surfaces
area of contact
shape of the surfaces
all of the above
1623. A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span-
এখানে,
w=1.2kg
I = 20m
T = 1500kg
আমরা জানি, T = wI²/8x
⇒ x = wI²/8T
= 1.2×20²/8x1500
=0.04m = 4cm
2.5cm
3.0cm
4.0cm
5.0cm
1624. Two coplanar couples having equal and opposite moments-
balance each other
produce a couple and an unbalanced force
are equivalent
can not balance each other
1625. In order to determine the effects of a fore, acting on a body we must know-
magnitude of the force
line of action of the force
nature of the force i, e whether the force is push or pull
all of these
1626. A solid cone has a height 'h', height of the CG of the cone above the base is-
h/4
2h/4
3h/4
4h/3
1627. In detennining stresses in frames by methods of sections, the frame is divided into two parts by an imaginary section drawn in such a way as not to cut more than-
two members with unknown forces of the frame
three members with unknown forces of the frame
four members with unknown forces of the frame
three members with known forces of the frame
1628. Moment of inertia about the base of a triangle of base 'B' and height '' is-
1/24 bh^4
1/18 bh^3
1/12 bh^3
1/6 bh^3
1629. force while acting on a body may-
change its motion
balance the forces already acting on it
give rise to the internal stresses in it
all of those
1630. If a suspended body is struck at the center of percussion, then the pressure on die axis passing through the point of suspension will be-
maximum
minimum
zero
infinity
1631. The product of either force of couple with the arm of the couple is called-
resultant couple
moment of the forces
resulting couple
moment of the couple
1632. A projectile is fired at an angle 9 to the vertical. Its horizontal range will be maximum when 9 is-
0°
30°
45°
60°
1633. The algebraic sum of moments of the forces. forming couple about any point in their plane is-
equal to the moment of the couple
constant
both of above are correct
both of above are wrong
1634. If rain is falling in the opposite direction of the movement of a pedestrain, he has to hold his umbrella-
more inclined when movirig
less inclined when moving
more inclined when standing
less inclined when standing
1635. The total motion possessed by a body is called-
impulsive force
mass
wight
momentum
1636. Which of the following do not have identical dimensions?
Momentum and impulse
Torque and energy
Torque and work
Moment of a force and angular momentum
1637. Concurrent forces are those forces whose lines of action-
lie on theme line
meet at one point
meet on the same plane
none of these
1638. The angle between two forces when the resultant is maximum and minimum respectively are-
0° and 180°
180° and 0°
90°
90° and 0°
1639. The maximum frictional force which comes into play when a body just begins to slide over another surface is called-
limiting friction
sliding friction
rolling friction
kinematic friction
1640. The rate of charge of displacement of a body is called.
Velocity
acceleration
momentum
none