Time of flight of a projectile on a horizontal plane, is
2u sinα/g
2u cosα/g
2u tanα/g
2u cotα/g
Correct Answer :
A. 2u sinα/g
Related Questions
Which one of the following statements is true?
The tangent of the angle of friction is equal to coefficient of friction
The angle of repose is equal to angle of friction
The tangent of the angle of repose is equal to coefficient of friction
All the above
A string of length 90 cm is fastened to two points A and B at the same level 60 cm apart. A ring weighing 120 g is slided on the string. A horizontal force P is applied to the ring such that it is in equilibrium vertically below B. The value of P is:
40 g
60 g
80 g
100 g
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
Joule is the unit of
Work
Force
Power
Torque
To attain the synchronous orbit, the launch of a satellite, is done from a place
On equator
On 30° latitude
On 45° latitude
On the poles
A square hole is punched out of a circular lamina, the diagonal of the square being the radius of the circle. If r is the radius of the circle, the C.G. of the remainder from the corner of the square on the circumference will be
[r (π + 0.25)]/(π - 0.5)
[r (π - 0.5)]/(π + 0.25)
[r (π - 0.25)]/(π - 0.5)
[r (π + 0.25)]/(π + 0.5)
The gravitational force makes a satellite go round the earth in a circular orbit, if it is projected with an initial velocity of
8.04 km/sec at a height of 285 km
11.11 km/sec at a height of 37,400 km
11.26 km/sec, the satellite escapes the pull of the earth
All the above
A weight of 100 kg is supported by a string whose ends are attached to pegs A and B at the same level shown in below figure. The tension in the string is 
50 kg
75 kg
100 kg
120 kg
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
In simple harmonic motion, acceleration of a particle is proportional to
Rate of change of velocity
Displacement
Velocity
Direction
A block in the shape of a parallelepiped of sides 1m × 2m × 3m lies on the surface. Which of the faces gives maximum stable block?
1 m × 2 m
2 m × 3 m
1 m × 3 m
Equally stable on all faces
The centre of gravity of a homogenous body is the point at which the whole
Volume of the body is assumed to be concentrated
Area of the surface of the body is assumed to be concentrated
Weight of the body is assumed to be concentrated
All the above
Pick up the correct statement from the following. The kinetic energy of a body
Before impact is equal to that after impact
Before impact is less than that after impact
Before impact is more than that after impact
Remain constant
The horizontal reaction at the support A of the structure shown in below figure, is
Zero
2 t
3 t
1 t
At a given instant ship A is travelling at 6 km/h due east and ship B is travelling at 8 km/h due north. The velocity of B relative to A is
7 km/hrs
2 km/hrs
1 km/hrs
10 km/hrs
The angle of projection at which the horizontal range and maximum height of a projectile are equal to
36°
45°
56°
76°
The Law of Polygon of Forces states that
If a polygon representing the forces acting at point in a body is closed, the forces are in equilibrium
If forces acting on a point can be represented in magnitude and direction by the sides of a polygon taken in order, then the resultant of the forces will be represented in magnitude and direction by the closing side of the polygon
If forces acting on a point can be represented of a polygon taken in order, their sides of a polygon taken in order, their resultant will be represented in magnitude and direction by the closing side of the polygon, taken in opposite order
If forces acting on a point can be represented in magnitude and direction by the sides of a polygon in order, the forces are in equilibrium
The length of a Second's pendulum, is
99.0 cm
99.4 cm
100 cm
101 cm
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
Newtons Law of Motion is:
Everybody continues in its state of rest or of uniform motion in a straight line, unless it is acted upon by some external force
The rate of change of momentum is directly proportional to the impressed force, and takes place in the same direction, in which the force acts
To every action, there is always an equal and opposite reaction
All the above
A particle is dropped from the top of a tower 60 m high and another is projected upwards from the foot of the tower to meet the first particle at a height of 15.9 m. The velocity of projection of the second particle is
16 m/sec
18 m/sec
20 m/sec
22 m/sec
In which of the following trusses, the method of substitution is required for determining the forces in all the members of the truss by graphic statics?
Howe truss
King post truss
Fink truss
Warren truss
From the circular plate of a diameter 6 cm is cut out a circular plate whose diameter is equal to radius of the plate. The C.G. of the remainder shifts from the original position through
0.25 cm
0.50 cm
0.75 cm
1.00 cm
The condition for a lifting machine to be reversible is that its efficiency should be
Less than 50%
More than 50%
More than 66.67%
Equal to 100%
The reaction at the support A of the beam shown in below figure is 
2 t
5.8 t
0.2 t
3.5 t
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)
Parallelogram Law of Forces states, if two forces acting simultaneously on a particle be represented in magnitude and direction by two adjacent sides of a parallelogram, their resultant may be represented in magnitude and direction by
Its longer side
Its shorter side
The diagonal of the parallelogram which does not pass through the point of intersection of the forces
The diagonal of the parallelogram which passes through the point of intersection of the forces
Instantaneous center is at infinity when the angular velocity is
Constant
Zero
Maximum
Minimum
Impulse can be obtained from a
Force-displacement diagram
Force-time diagram
Velocity-time diagram
Velocity-displacement diagram
A ball of mass 250 g moving on a smooth horizontal table with a velocity of 10 m/sec hits an identical stationary ball B on the table. If the impact is perfectly plastic, the velocity of the ball B just after impact would be
Zero
5 m/sec
10 m/sec
None of these