Pick up the correct statement from the following. A rubber ball when strikes a wall rebounds but a lead ball of same mass and velocity when strikes the same wall, falls down
Rubber and lead balls undergo equal changes in momentum
Change in momentum suffered by lead ball is less that of rubber ball
Momentum of rubber ball is less than that of lead ball
None of these
Correct Answer :
D. None of these
Related Questions
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
Cartesian form of the equation of catenary is
y = c cosh x/c
y = c sinh x/c
y = c tan x/c
y = c sin x/c
The unit of rotational inertia of a body in C.G.S system is
cm4
kg.cm²
gm.cm²
gm.cm3
A system of coplanar forces is in equilibrium when
Force polygon closes
Funicular polygon closes
Both force polygon and funicular polygon close
All the forces are concurrent
The following is not a law of static friction:
The force of friction always acts in a direction opposite to that in which the body tends to move
The force of friction is dependent upon the area of contact
The force of friction depends upon the roughness of the surface
The magnitude of the limiting friction bears a constant ratio to the normal reaction between two surfaces
The acceleration of a train starting from rest at any instant is 1/6(V + 1) m/sec² where V is the velocity of the train in m/sec. The train will attain a velocity of 36 km/hour after travelling a distance of
2000 m
2100 m
2200 m
2300 m
One end of an elastic string of natural length / and modulus X is kept fixed while to the other end is attached a particle of mass m which is hanging freely under gravity. The particle is pulled down vertically through a distance x, held at rest and then released. The motion is
A simple harmonic motion
A rectilinear motion with constant speed
A damped oscillatory motion
None of the above
If α is the angular acceleration of a compound pendulum whose angular displacement is θ, the frequency of the motion is
2π √(α/θ)
(1/2π) √(α/θ)
4π √(α/θ)
2π √(α - θ)
A uniform pyramid and a uniform prism of same height lie with their base on the surface. Which is more stable?
Pyramid
Prism
Both equally stable
None of the above
A body is dropped from a height of 100 m and at the same time another body is projected vertically upward with a velocity of 10 m/sec. The two particles will
Never meet
Meet after 1 sec
Meet after 5 sec
Meet after 10 sec
In a simple screw jack, the pitch of the screw is 9 mm and length of the handle operating the screw is 45 cm. The velocity ratio of the system is
1.5
5
25
314
A ball of mass 1 kg moving with a velocity of 2 m/sec collides a stationary ball of mass 2 kg and comes to rest after impact. The velocity of the second ball after impact will be
Zero
0.5 m/sec
1.0 m/sec
2.0 m/sec
If the resultant of two forces P and Q acting at an angle θ makes an angle α with P, then tan α equals
P sin θ/P - Q cos θ
Q sin θ/P + Q cos θ
P sin θ/P + Q tan θ
Q sin θ/P + Q sin θ
A 2 m long ladder rests against a wall and makes an angle of 30° with the horizontal floor. Where will be the instantaneous center of rotation when the ladder starts slipping? (i) 1.0 in from the wall (ii) 1.732 m from the wall (iii) 1.0 m above the floor (iv) 1.732 m above the floor The correct answer is
(i) and (iii)
(i) and (iv)
(ii) and (iii)
(ii) and (iv)
When a body moves round a fixed axis, it has
A rotary motion
A circular motion
A translatory
A rotary motion and translatory motion
A cable loaded with 10 kN/m of span is stretched between supports in the same horizontal line 100 m apart. If the central dip is 10 m, then the maximum and minimum pull in the cable respectively are
1346.3 kN and 1500 kN
1436.2 kN and 1250 kN
1346.3 kN and 1250 kN
1436.2 kN and 1500 kN
Varingons theorem of moments states
Arithmetical sum of the moments of two forces about any point, is equal to the moments of their resultant about that point
Algebraic sum of the moments of two forces about any point, is equal to the moment of their resultant about that point
Arithmetical sum of the moments of the forces about any point in their plane, is equal to the moment of their resultant about that point
Algebraic sum of the moments of the forces about any point in their plane, is equal to the moment of their resultant about that point
If a particle moves with a uniform angular velocity ω radians/sec along the circumference of a circle of radius r, the equation for the velocity of the particle, is
v = ω √(y² - r²)
y = ω √(y - r)
v = ω √(r² + y²)
v = ω √(r² - y²)
When a body slides down an inclined surface, the acceleration (f) of the body, is given by
f = g
f = g sin θ
f = g cos θ
f = g tan θ
Joule is the unit of
Work
Force
Power
Torque
Power developed by a torque, is
2πNT kg m/min
2πNT/4500 h.p
2πNT /60 watts
All the above
A stone of mass 1 kg is tied to a string of length 1 m and whirled in a horizontal circle at a constant angular speed 5 rad/sec. The tension in the string is,
5 N
10 N
15 N
25 N
At the instantaneous center, the velocity of the moving lamina at any instant is
Zero
Maximum
Minimum
Varying
Two forces of 6 Newtons and 8 Newtons which are acting at right angles to each other, will have a resultant of
5 Newtons
8 Newtons
10 Newtons
12 Newtons
A particle moves with a velocity of 2 m/sec in a straight line with a negative acceleration of 0.1 m/sec2. Time required to traverse a distance of 1.5 m, is
40 sec
30 sec
20 sec
15 sec
A Seconds pendulum executes
0.5 beat per second
1.0 beat per second
2.0 beats per second
2.5 beats per second
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 locus of the instantaneous centre of a moving rigid body, is
Straight line
Involute
Centroid
Spiral
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
A ball which is thrown upwards, returns to the ground describing a parabolic path during its flight
Vertical component of velocity remains constant
Horizontal component of velocity remains constant
Speed of the ball remains constant
Kinetic energy of the ball remains constant