Ball A of mass 250 g moving on a smooth horizontal table with a velocity of 10 m/s hits an identical stationary ball B on the table. If the impact is perfectly elastic, the velocity of the ball B just after impact would be
Zero
5 m/sec
10 m/sec
None of these
Correct Answer :
C. 10 m/sec
Related Questions
For lifting a load of 50 kg through a distance of 2.5 cm, an effort of 12.5 kg is moved through a distance of 40 cm. The efficiency of the lifting machine, is
60 %
65 %
70 %
75 %
Effect of a force on a body depends upon its
Direction
Magnitude
Position
All the above
A retarding force on a body does not
Change the motion of the body
Retard the motion of the body
Introduce the motion of the body
None of these
The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm, about centroidal axis, is
437.5 cm4
337.5 cm4
237.5 cm4
137.5 cm4
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
If the angle of projection is double the angle of inclination (α) of the plane on which particle is projected, the ratio of times of flight up the inclined plane and down the inclined plane, will be
½ cos α
½ sin α
½ tan α
2 cos α
Williot-Mohr diagram is used to determine deflection in
Trusses only
Beam only
Rigid frames only
Any type of structure
The centre of gravity of the trapezium as shown in below figure from the side is at a distance of
(h/3) × [(b + 2a)/(b + a)]
(h/3) × [(2b + a)/(b + a)]
(h/2) × [(b + 2a)/(b + a)]
(h/2) × [(2b + a)/(b + a)]
A simple pendulum of length 1 has an energy E when its amplitude is A. If its amplitude is increased to 2 A, the energy becomes
E
E/2
2E
4E
μ is coefficient of friction. A wheeled vehicle travelling on a circular level track will slip and overturn simultaneously if the ratio of its wheel distance to the height of its centroid, is
μ
2μ
3μ
½μ
Moment of inertia of a squares of side b about an axis through its centre of gravity, is
b3/4
b4/12
b4/3
b4/8
If the radius of the earth is 600 km the height of a mountain above sea level at the top of which a beat seconds pendulum at sea level, looses 27 seconds a day, is
500 metres
1000 metres
1500 metres
2000 metres
The torque produced by a force depends on (i) The magnitude of the force (ii) The direction of the force (iii) The point of application of the force relative to origin The correct answer is
Only (i)
Both (i) and (ii)
Both (i) and (iii)
All (i), (ii) and (iii)
The motion of a particle moving with S.H.M. from an extremity to the other, constitutes
Half an oscillation
One full oscillation
Two oscillations
None of these
A particle of mass 2 kg executes simple harmonic motion of frequency 6/71 Hz and amplitude 0.25 m. Its maximum kinetic energy is
4.5 J
9.0 J
12.0 J
18.0 J
The unit of Moment of Inertia of a body, is
m
m2
m3
m4
The intrinsic equation of catenary is
S = c tan ψ
y = c cosh x/c
y = c cosh ψ
y = c sinh ψ
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
Work may be defined as
Force × distance
Force × velocity
Force × acceleration
None of these
A Seconds pendulum executes
0.5 beat per second
1.0 beat per second
2.0 beats per second
2.5 beats per second
Lami's theorem states that
Three forces acting at a point are always in equilibrium
If three forces acting on a point can be represented in magnitude and direction by the sides of a triangle, the point will be in the state of equilibrium
Three coplanar forces acting at a point will be in equilibrium, if each force is proportional to the sine of the angle between the other two
Three coplanar forces acting at a point will be in equilibrium if each force is inversely proportional to the sine of the angle between the other two
For the given values of initial velocity of projection and angle of inclination of the plane, the maximum range for a projectile projected upwards will be obtained, if the angle of projection is
α = π/4 - β/2
α = π/2 + β/2
α = β/2 - π/2
α = π/4 - β/2
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
The velocity ratio of the differential wheel and axle is
R/r1 - r2
2R/r1
3R/r1 - r2
2R/r1 + r2
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
The C.G. of a thin hollow cone of height h, above its base lies on the axis, at a height of
h/3
h/4
2h/3
3h/4
Power developed by a torque, is
2πNT kg m/min
2πNT/4500 h.p
2πNT /60 watts
All the above
A circular disc rotates at n rpm. The angular velocity of a circular ring of same mass and radius as the disc and to have the same angular momentum is
n rpm
n/2 rpm
n/4 rpm
2n rpm
The piston of a steam engine moves with a simple harmonic motion. The crank rotates 120 r.p.m. and the stroke length is 2 metres. The linear velocity of the piston when it is at a distance of 0.5 metre from the centre, is
5.88 m/sec
8.88 m/sec
10.88 m/sec
12.88 m/sec
The load shared by the member BC of the structure shown in below figure is
23 t
32 t
4 t
3 t