If a projectile is fired with an initial velocity of 10 m/sec at an angle of 60° to the horizontal, its horizontal and vertical velocity at the highest point of trajectory are
0 and 5 m/sec
5 m/sec and 0
5√3 m/sec and 0
5 and 5√3 m/sec
Correct Answer :
B. 5 m/sec and 0
Related Questions
The forces which meet at one point and have their lines of action in different planes are called
Coplanar non-concurrent forces
Non-coplanar concurrent forces
Non-coplanar non-current forces
Intersecting forces
A ladder of weight 'w' rests against a smooth vertical wall, and rests on rough horizontal ground, the coefficient of friction between the ladder and the ground being 1/4. The maximum angle of inclination of the ladder to the vertical, if a man of weight 'w' is to walk to the top of it safely, is tan'1 x, where x is
1/4
1/3
3
4
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
The ratio of the moment of inertia of a rectangle about its centroidal axis to the moment of inertia about its base, is
1/4
1/2
3/4
2
For a simple pendulum, the period of one oscillation is
2π √(l/2g)
2π √(2g/l)
2π √(l/g)
2π √(g/2l)
If G is the Gauge of track, v is velocity of the moving vehicle, g is the acceleration due to gravity and r is the radius of a circular path, the required super elevation is
gv²/Gr
Gr²/gr
Gr²/gv²
Gv²/gv
Engineer's units of force, is
Newton in absolute units
Dyne in absolute units
Newton and dyne in absolute units
All the above
The characteristic of a couple is:
Algebraic sum of forces, constituting a couple is zero
Algebraic sum of moments of forces, constituting a couple, about any point, is same
A couple can be never the balanced by a single force
All the above
In simple harmonic motion, acceleration of a particle is proportional to
Rate of change of velocity
Displacement
Velocity
Direction
The practical units of work, is
Erg
Joule
Newton
Dyne
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
Force polygon method is applicable for
Any coplanar force system
A system of parallel forces only
Concurrent coplanar force system
Non-concurrent coplanar force system
M.I. of solid sphere, is
Mr2
½ Mr2
Mr2
πr4/2
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 satellite goes on moving along its orbit round the earth due to
Gravitational force
Centrifugal force
Centripetal force
None of these
P is the force acting on a body whose mass is m and acceleration is f. The equation P - mf= 0, is known as
Equation of dynamics
Equation of dynamic equilibrium
Equation of statics
None of these
Two circular discs of same weight and thickness are made from metals having different densities. Which disc will have the larger rotational inertia about its central axis?
Disc with larger density
Disc with smaller density
Both discs will have same rotational inertia
None of the above
The centre of gravity of a plane lamina will not be at its geometrical centre if it is a
Circle
Equilateral triangle
Rectangle
Right angled triangle
The centre of gravity of a trapezoidal dam section whose top width is a, bottom width is band the vertical side is a, from its vertical face is
(a² + ab + b²)/3 (a + b)
(b² + bc + c²)/3 (b + c)
(a² + ab + c²)/3 (a + c)
None of these
The product of mass and velocity of a moving a body, is called
Moment
Momentum
Power
Impulse
The height at which the end of a rope of length l should be tied so that a man pulling at the other end may have the greatest tendency to overturn the pillar, is
¾ l
½ l
l/√2
2/√3 l
A glass ball is shot to hit a wall from a point on a smooth floor. If the ball returns back to the point of projection in twice the time taken in reaching the wall, the coefficient of restitution between the glass ball and the wall is
0.25
0.33
0.40
0.50
Centre of gravity of a thin hollow cone lies on the axis of symmetry at a height of
One-half of the total height above base
One-third of the total height above base
One-fourth of the total height above base
None of these
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
The instantaneous centre of a member lies at the point of intersection of two lines drawn at the ends of the member such that the lines are inclined to the direction of motion of the ends at
30°
45°
60°
90°
A 50 kg boy climbs up a 8 m rope in gymnasium in 10 sec. The average power developed by the boy is approximately
400 watts
500 watts
4000 watts
None of these
Which of the following represents the state of neutral equilibrium?
A cube resting on one edge
A smooth cylinder lying on a curved surface
A smooth cylinder lying on a convex surface
None of the above
The following is in unstable equilibrium
A uniform solid cone resting on a generator on a smooth horizontal plane
A uniform solid cone resting on its base on a horizontal plane
A solid cube resting on one edge
A satellite encircling the earth
When two forces, each equal to P, act at 90° to each other, then the resultant will be
P
P√2
P/√2
2P
The diagram showing the point of application and line of action of forces in their plane is called
Vector diagram
Space diagram
Force diagram
Funicular diagram