121. If three coplaner forces acting on a point are in equilibrium, then each force is proportional to the sine, of the angle between the other two.
Correct
Incorrect
✅ The correct answer is option A.
Engineering Mechanics MCQs
123. The rate of doing work is known as
potential energy
kinetic energy
power
none of these
✅ The correct answer is option C.
124. A number of forces acting at a point will be in equilibrium, if
all the forces are equally inclined
sum of all the forces is zero
sumof resolved parts in the vertical direction is zero (i.e. ∑V = 0)
none of these
✅ The correct answer is option C.
125. The maximum acceleration of a particle moving with simple harmonic motion is
ω
ωr
ω2r
ω/r
✅ The correct answer is option C.
126. The efficiency of a lifting machine is the ratio of
output to the input
work done by the machine to the work done on the machine
mechanical advantage to the velocity ratio
all of the above
✅ The correct answer is option D.
127. Coplaner non-concurrent forces are those forces which __________ at one point, but their lines of action lie on the same plane.
meet
do not meet
✅ The correct answer is option B.
128. A block of mass m1, placed on an inclined smooth plane is connected by a light string passing over a smooth pulley to mass m2, which moves vertically downwards as shown in the below figure. The tension in the string is
m1/m2
m1.g sin α
m1.m2/m1+m2
✅ The correct answer is option D.
129. A couple produces
translatory motion
rotational motion
combined translatory and rotational motion
none of the above
✅ The correct answer is option B.
130. The coefficient of restitution for inelastic bodies is
zero
one
between zero and one
more than one
✅ The correct answer is option A.