EXERCISE-III
Q.l 	 Two particles are projected from the same point with the same speed, .at different angles 8 1 and
        O2 to the horizontal. They have the same horizontal range. Their times of flight are tl and ~
        respectively :
          (1) 0 1 + 92 = 900        (2) -' = tanO            (3)
                                                                    t1 	
                                                                    -=     tan 0                       t1    --.!L
                                          t2            I           t2             2            (4) sin9i - sin92
                                                                                        2                    2
 Q.2 	 A particle moves along the positive branch of the curve y = x                          where x = ~ , where x and y
                                                                                        2
          are measured in metre and t in second. At t        =    2 sec, the velocity of the particle is :
          (1)   (21-41) mlsec       (2)   (21+4]) mlsec      (3)   (21 +21) mlsec              (4)   (41 -2]) mlsec
 Q.3 	    A cannon ball has a range R on a horizontal plane. If h and h' are the greatest h~ights in the two
          paths for which this is possible, then :
          (1) R = 4 .j(hh')         (2) R = 4h               (3) R = 4 h h'                    (4) R        JW
                                                 h' 	
 QA 	 When a particle is thrown horizontally, the resultant velocity of the projectile at any time t is
      given by :
          (1)gt 	                  (2) igt2                 (3)    Ju2 +g2 t 2                 (4)   Ju2    g2 t 2
Q.5 	 A particle is thrown with a speed u at an angle 8 with the horizontal. When the particle makes an.
      angle ~ with the horizontal, its speed changes to v :
         (1) v = ucos 0 	                                   (2) v = ucosO .            cos~
         (3) v = 	ucosO .   sec~                            (4) v     = usecO    .     cos~
Q.6 	 If retardation produced by air resistances to projectile is one-tenth of acceleration due to gravity,
      the time to reach maximum height approximately :
      (1) increase by 9% (2) decrease by 9% (3) increase by 11%              (4) decrease by 11%
Q.7 	 Find the average velocity of a projectile between the instants it crosses half the maximum height.
         It is projected with a speed u at an angle 0 with the horizontal :
         (1) u cos 0               (2) u sin 0              (3) u 	                            (4) u'tan 0
Q.8 	    A particle starts from the origin of coordinates at time t 0 and moves in the xy plane with a
         constant acceleration ex. in the y-direction. Its equation of motion is y := px2• Its velocity
         component in the x-direction is :-     .
         (1) variable              (2)
                                          ~
                                          VP
                                                                a
                                                            (3) 2P 	                          (4)    Hi
 AssertiorilReason Type Questions:
 Q.9 	 Statement-I: Two balls ofdifferent masses are thrown verticallyup with same speed. They will pass
       through their point· ofproj ection in downward direction with the same speed.
       Statement-2: The maximum height and downward velocity attained at the point ofprojection are
         independent ofthe mass ofthe ball.
         ,(1) Ifboth Statement-I and Statement-2 are true, and Statement-2 is the correct explanation of
               Statement-I.
          (2) If both Statement-l and Statement-2 are true but Statement-2 is not the correct explanation of
               Statement-I.
         (3) If Statement-I is true but Statemeht-2 is false.
         (4) If Statement-I is false but Statement-2 is true.
 Q.IO 	 Statement-I: Forangle ofprojectiontan-I (4), the horizontal range and maximum height are equal. 
        Statement 2 : The maximum range ofprojectile is directly proportional to square of velocity and 
        inversely proportional to accelemtion ofgmvity. 
        (1) Ifboth Statement-I and Statement-2 are true, and Statement-2 is the correct explanation of
             Statement-I.
        (2) If both Statement-I and Statement-2 are true but Statement-2 is not the correct explanation of
             Statement-I . 
       . (3) If Statement-I is true but Statement-2 is false. 
         (4) If Statement-I is false but Statement-2 is true.
Column matching Type Question:
                                                                       ,	     2
Q.l1 	 Trajectory ofparticle in a projectile motion is given as: y = x - x . Here, x and y are in metres. For
                                                                             80   .
        this projectile motion match the followingwithg= i 0 mls2·
        Column-J 	                                       Column-ll
        (A) Angle ofprojection 	                          (p)20m
        (B)Angle ofvelocitywith                           (Q)80m
                                                                                                                ~
            horizontal after 4s
        (C) Maximum height 	                              (R)45°
       (D) Horizontal range 	                             (S)tan- l   (~),