A projectile fired with initial velocity u at some angle θ has a range R. If the initial velocity be doubled at the same angle of projection, then the range will be

1. 2 R

2. R/2

3. R

4. 4 R

If the initial velocity of a projectile be doubled, keeping the angle of projection same, the maximum height reached by it will

(1) Remain the same

(2) Be doubled

(3) Be quadrupled

(4) Be halved

In the motion of a projectile freely under gravity, its

(1) Total energy is conserved

(2) Momentum is conserved

(3) Energy and momentum both are conserved

(4) None is conserved

The range of a projectile for a given initial velocity is maximum when the angle of projection is 45°. The range will be minimum, if the angle of projection is

(1) 90°

(2) 180°

(3) 60°

(4) 75°

A ball is thrown upwards and it returns to the ground describing a parabolic path. Which of the following remains constant?

(1) Kinetic energy of the ball

(2) Speed of the ball

(3) Horizontal component of velocity

(4) Vertical component of velocity

At the top of the trajectory of a projectile, the directions of its velocity and acceleration are:

An object is thrown along a direction inclined at an angle of 45° with the horizontal direction. The horizontal range of the particle is equal to 

(1) Vertical height

(2) Twice the vertical height

(3) Thrice the vertical height

(4) Four times the vertical height

The height y and the distance x along the vertical plane of a projectile on a certain planet (with no surrounding atmosphere) are given by $y=(8t-5t^2)$ meter and x = 6t meter, where t is in second. The velocity with which the projectile is projected is 

(1) 8 m/sec

(2) 6 m/sec

(3) 10 m/sec

(4) Not obtainable from the data

The range of a particle when launched at an angle of 15° with the horizontal is 1.5 km. What is the range of the projectile when launched at an angle of 45° to the horizontal 

(1) 1.5 km

(2) 3.0 km

(3) 6.0 km

(4) 0.75 km

A projectile thrown with a speed v at an angle θ has a range R on the surface of earth. For same v and θ, its range on the surface of moon will be (acceleration due to gravity on moon=$\frac{g}{6}$):

(1) R/6

(2) 6 R

(3) R/36

(4) 36 R