A spring scale in a stationary lift shows a reading of 60 kg for a man standing on it. If the lift starts descending at an acceleration of g/5, the scale reading would be
48 kg
60 kg
72 kg
None of these
Correct Answer :
A. 48 kg
Related Questions
If the direction of projection bisects the angle between the vertical and the inclined plane, then the range of projectile on the inclined plane is
Zero
Maximum
Minimum
None of these
The practical units of work, is
Erg
Joule
Newton
Dyne
The maximum value of the horizontal range for a projectile projected with a velocity of 98 m/sec is
98 m
490 m
980 m
1960 m
From a solid cylinder of height 8 cm and radius 4 cm, a right circular cone is scooped out on the same base and having the same height as that of the cylinder. The C.G. of the remainder is at a height of
4.5 cm
5.0 cm
5.25 cm
5.5 cm
The Centre of gravity of a 10 × 15 × 5 cm T-section from its bottom, is
7.5 cm
5.0 cm
8.75 cm
7.85 cm
If the given forces P₁, P₂, P₃ and P₄ are such that the force polygon does not close, then the system will
Be in equilibrium
Always reduce to a resultant force
Always reduce to a couple
Both (A) and (C)
According to Law of Triangle of Forces
Three forces acting at a point, can be rep-resented by the sides of a triangle, each side being in proportion to the force
Three forces acting along the sides of a triangle are always in equilibrium
If three forces acting on a, point can be represented in magnitude and direction, by the sides of a triangle taken in order, these will be in equilibrium
If the forces acting on a particle be represented in magnitude and direction by the two sides of a triangle taken in order, their resultant will be represented in magnitude and direction by the third side of the triangle, taken in opposite order
If a body moves in such a way that its velocity increases by equal amount in equal intervals of time, it is said to be moving with
A uniform retardation
A uniform acceleration
A variable acceleration
A variable retardation
The pole distance is measured in
Distance scale
Force scale
Mass scale
Time scale
The angular speed of a car while taking a circular turn of radius 100 m at 36 km/hour, is
0.1 radian/sec
1 radian/sec
100 radian/sec
1000 radian/sec
The motion of a particle is described by the relation x = t2- 10t + 30, where x is in metres and t in seconds. The total distance travelled by the particle from t = 0 to t = 10 seconds would be
Zero
30 m
50 m
60 m
The apparent weight of a man in a moving lift is less than his real weight when it is going down with
Uniform speed
An acceleration
Linear momentum
Retardation
A ball is dropped from a height of 2.25 m on a smooth floor and rises to a height of 1.00 m after the bounce. The coefficient of restitution between the ball and the floor is
0.33
0.44
0.57
0.67
A particle moves in a straight line and its position is defined by the equation x = 6 t² - t3 where t is expressed in seconds and x in meters. The maximum velocity during the motion is
6 m/sec
12 m/sec
24 m/sec
48 m/sec
Select the correct statement
The body centrode rolls on the space centrode
The space centrode rolls on the body centrode
Both body and space centrodes may role on each other
The body centrode never touches space centrode
The reaction at the central support B of the beam ABC hinged at D shown in below figure is 
2 t
5.8 t
0.2 t
3.5 t
A projectile is thrown at an angle α to the horizontal with velocity v. It will have the maximum centripetal acceleration
At the start
At the top of the trajectory
As it strikes the ground
Elsewhere
Power developed by a torque, is
2πNT kg m/min
2πNT/4500 h.p
2πNT /60 watts
All the above
If two forces are in equilibrium, then the forces must (i) Be equal in magnitude (ii) Be opposite in sense (iii) Act along the same line The correct answer is
(i) and (ii)
(i) and (iii)
Only (i)
All (i), (ii) and (iii)
The reaction at the support D of the continuous beam ABCD, hinged at two points shown in below figure is 
1.6 t
1.6 t ↓
0.5 t
0.5 t ↓
Pick up the correct statement from the following for the structure shown in below figure.
The horizontal reaction at A is 2 √3t ←
The horizontal reaction at C is 2 √3t →
The vertical reaction at A is zero
All the above
Two forces act an angle of 120°. If the greater force is 50 kg and their resultant is perpendicular to the smaller force, the smaller force is
20 kg
25 kg
30 kg
35 kg
When a body falls freely under gravitational force, it possesses
Maximum weight
Minimum weight
No weight
No effect on its weight
The inherent property of a body which offers reluctance to change its state of rest or uniform motion, is
Weight
Mass
Inertia
Momentum
One Newton force, is
103 dynes
104 dynes
105 dynes
106 dynes
If two forces acting at a point are in equilibrium, they must be equal in magnitude and their line of action must be along
The same line in the same sense
The same line in opposite sense
The perpendicular to both the lines
None of these
The moment of inertia of a triangular section (base b, height h) about centroidal axis parallel to the base, is
b3h/12
bh3/3
bh3/36
bh3/2
Time of flight of a projectile on a horizontal plane, is
2u sinα/g
2u cosα/g
2u tanα/g
2u cotα/g
Pick up the correct statement from the following:
If two equal and perfectly elastic smooth spheres impinge directly, they interchange their velocities
If a sphere impinges directly on an equal sphere which is at rest, then a fraction ½(1 - e2) the original kinetic energy is lost by the impact
If two equal spheres which are perfectly elastic impinge at right angles, their direction after impact will still be at right angles
All the above
To avoid bending action at the base of a pier,
Suspension and anchor cables are kept at the same level
Suspension and anchor cables are fixed to pier top
Suspension cable and anchor cables are attached to a saddle mounted on rollers on top of the pier
None the these