A projectile has maximum range of 40 m on a horizontal plane. If angle of projection is a and the time of flight is 1 second, then sin a must be about (Assume g = 10 m/sec²)
1/4
1/3
1/2
1/5
Correct Answer :
A. 1/4
Related Questions
At the instantaneous center, the velocity of the moving lamina at any instant is
Zero
Maximum
Minimum
Varying
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 graphical method of determining the forces in the members of a truss is based on
Method of joint
Method of section
Either method
None of the two methods
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
A particle is executing simple harmonic motion in a line 1.0 m long. If the time of one complete vibration is 1 sec, then the maximum velocity of the particle is
1.00 m/sec
1.57 m/sec
3.14 m/sec
6.28 m/sec
Power can be expressed as
Work/energy
Work/time
Work × time
Work/distance
In a simple harmonic motion, the position of equilibrium is always
Stable
Unstable
Neutral
None of the above
The ratio of the reactions RA and RB of a simply supported beam shown in below figure is 
0.50
0.40
0.67
1.00
The reaction at the support B of the beam shown in below figure is 
1.6 t
9.6 t
8.5 t
0.5 t
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
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
The shape of a suspended cable for a uniformly distributed load over it is
Circular
Parabolic
Catenary
Cubic parabola
Williot-Mohr diagram is used to determine deflection in
Trusses only
Beam only
Rigid frames only
Any type of structure
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
A bullet weighing 200 g is fired horizontally with a velocity of 25 m/sec from a gun carried on a carriage which together with the gun weighs 100 kg. The velocity of recoil of the gun, will be
0.01 m/sec
0.05 m/sec
1.00 m/sec
1.5 m/see
A ball is dropped from a height of 16 m on a horizontal floor. If it rebounds to a height of 9 m after striking the floor, the coefficient of restitution between ball and floor is
1/4
2/3
3/4
4/3
A load of 500 kg was lifted through a distance of 13 cm. by an effort of 25 kg which moved through a distance of 650 cm. The efficiency of the lifting machine is
50 %
40 %
55 %
30 %
A 49 kg lady stands on a spring scale in an elevator. During the first 5 sec, starting from rest, the scale reads 69 kg. The velocity of the elevator will be
10 m/sec
15 m/sec
20 m/sec
25 m/sec
On a mass m describing a circular path of radius r, the centrifugal force
Acts tangentially to the circular path
Acts towards the centre of rotation
Acts away from the centre of rotation
Is mw2r/g kgf
A projectile has maximum range of 40 m on a horizontal plane. If angle of projection is a and the time of flight is 1 second, then sin a must be about (Assume g = 10 m/sec²)
1/4
1/3
1/2
1/5
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
For perfectly elastic bodies, the value of coefficient of restitution is
Zero
0.5
1.0
Between 0 and 1
In a lifting machine with efficiency 60%, an effort of 200 N is required to raise a load of 6 kN. The velocity ratio of the machine is
30
50
60
80
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
A funicular polygon cannot be made to pass through
One specified point
Two specified points
Three specified points
More than three specified points
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
Time required to stop a car moving with a velocity 20 m/sec within a distance of 40 m, is
2 sec
3 sec
4 sec
5 sec
The units of inertia of mass are
kg/m
kg/m2
m4
kg-m2
The unit of moments in M.K.S system, is
kg.m
kg/m2
kg/sec2
kg/sec
Newton's law of Collision of elastic bodies states that when two moving bodies collide each other, their velocity of separation
Is directly proportional to their velocity of approach
Is inversely proportional to their velocity of approach
Bears a constant ratio to their velocity of approach
Is equal to the sum of their velocities of approach