A projectile is fired at an angle 9 to the vertical. Its horizontal range will be maximum when 9 is_________________?

Related Mcqs:

1. A semi-circular disc rests on a horizontal surface with its top flat surface horizontal and circular portion touching down. The coefficient of friction between semi-cricular disc and horizontal surface is i. This disc is to be pulled by a horizontal force applied at one edge and it always remains horizontal. When the disc is about to start moving, its top horizontal force will____________________?

   A. remain horizontal
   B. slant up towards direction of pull
   C. slant down towards direction of pull
   D. unpredictable
   E. none of the above

2. The angle which an inclined plane makes with the horizontal when a body placed on it is about to move down is known as angle of__________________?

   A. friction
   B. limiting friction
   C. repose
   D. kinematic friction
   E. static friction

3. The M.I. of hollow circular section about a central axis perpendicular to section as compared to its M.I. about horizontal axis is_________________?

   A. same
   B. double
   C. half
   D. four times
   E. one fourth

4. The effort required to lift a load W on a screw jack with helix angle a and angle of friction <j) is equal to_________________?

   A. Wtan(a + )
   B. Wtan(a-)
   C. Wcos(a + )
   D. Wsin(a + )
   E. W (sin a + cos )

5. A heavy string attached at two ends at same horizontal level and when central dip is very small approaches the following curve___________________?

   A. catenary
   B. parabola
   C. hyperbola
   D. elliptical
   E. circular arc

6. The centre of percussion of a solid cylinder of radius r resting on a horizontal plane will be______________?

   A. r/2
   B. 2r/3
   C. r/A
   D. 3r/2
   E. 3r/A

7. A body of weight W on inclined plane of a being pulled up by a horizontal force P will be on the point of motion up the plane when P is equal to___________________?

   A. W
   B. W sin (a + $)
   C. Wtan(a + <|))
   D. Wan(a-)
   E. Wtana

8. A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span________________?

   A. 2.5 cm
   B. 3.0 cm
   C. 4.0 cm
   D. 5.0 cm
   E. 2.0 cm

9. On a ladder resting on smooth ground and leaning against vertical wall, the force of friction will be__________________?

   A. towards the wall at its upper end
   B. away from the wall at its upper end
   C. upwards at its upper end
   D. downwards at its upper end
   E. none of the above

10. A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if______________?

    A. the floor is smooth, the wall is rough
    B. the floor is rough, the wall is smooth
    C. the floor and wall both are smooth surfaces
    D. the floor and wall both are rough sur-faces
    E. will be in equilibrium under all condi-tions