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An object launched
into space without
motive power of its
own is called a
projectile.
Projectile motion horizontal
Projectile motion horizontal
a
Projectile motion horizontal
Projectile motion horizontal
PROJECTILE MOTION CHARACTERISTICS
The projectile has:
•a constant horizontal velocity and
•a vertical velocity that changes uniformly under
 the influence of gravity.
If an object is projected horizontally, its motion can best
be described by considering its horizontal and vertical
motion separately. In the figure we can see that the
vertical velocity and position increase with time as those
of a free-falling body.

Note that the
horizontal distance
increases linearly
with time, indicating
a constant
horizontal velocity.
Projectile motion horizontal
Take this basketball shot as an example. Notice the
horizontal velocity of the ball. Look at the spacing of the
vertical lines which mark the position of the ball every 10th of
a second. The spacing is quite consistent, which indicates a
constant horizontal velocity.
HORIZONTAL MOTION

Velocity (vx) is constant

       Velocity
                                  x
                            vx
                                  t
       Distance
                            x    vx t

       Time                      x
                             t
                                 vx
VERTICAL MOTION

Velocity (vy) increases under the acceleration due to gravity.

    Velocity

     voy   0       vy     gt
    Distance
                         1 2
                    y      gt
                         2
    Time
                          2y
                    t
                          g
RESULTANT VELOCITY

The resultant velocity can be found using the Pythagorean
theorem.

                               2            2
              vR       (vx )       (v y )
3.6 A ball is thrown horizontally with a velocity of 12 m/s.
How far has the ball fallen 2 s later?

  HORIZONTAL          VERTICAL
  vox = 12 m/s        voy = 0 m/s
  t=2s                g = 9.8 m/s2
                      t=2s


     vox = vx            y = ½ gt2
     x = vx t              = ½ (9.8)(2)2
       = 12(2)             = 19.6 m
       = 24 m
3.7 A rifle with a muzzle velocity of 200 m/s is fired with its barrel
horizontally at a height of 1.5 m above the ground.
a. How long is the bullet in the air?

  HORIZONTAL          VERTICAL
  vox = 200 m/s       voy = 0 m/s
                      y = 1.5 m
                                              1 2
                                         y      gt
                      g = 9.8 m/s2            2


                2y         2(1.5)
         t                        = 0.55 s
                g           9 .8
b. How far away from the rifle does the bullet strike the ground?

                       x = vx t
                         = 200(0.55)
                         = 110 m
3.8 A ball is rolled off the edge of a table 1 m high with a horizontal
velocity of 1.8 m/s. With what velocity does it strike the floor?
   HORIZONTAL            VERTICAL
   vox = 1.8 m/s         voy = 0 m/s
                         y=1m
                         g = 9.8 m/s2
                                                              2     2
   We need to find the resultant velocity: v f               vx    vy

   Where:                               1 2
   vx = vox = 1.8 m/s             y       gt
                                        2
   vy = voy + gt
                                  2y        2(1)
                            t                    = 0.45 s
                                  g         9 .8
vy = 0 + 9.8(0.45)
   = 4.4 m/s


vf      (1.8) 2   (4.4) 2 = 4.75 m/s
THE MONKEY AND THE ZOOKEEPER
The monkey spends most of its day hanging
from a branch of a tree.
The zookeeper feeds the monkey by
shooting bananas from a banana cannon to
the monkey in the tree.
The monkey usually drops from the tree the
moment that the banana leaves the muzzle
of the cannon.
The zookeeper is faced with the dilemma of
where to aim the banana cannon in order to
feed the monkey. If the monkey lets go of
the tree the moment that the banana is
fired, then where should he aim the banana
cannon?
The zookeeper aims above the monkey (perhaps he
presumes that gravity will accelerate the banana downward
such that it hits the monkey). What would be the path of the
banana? Would the banana hit the monkey?



                                   Since both banana and
                                   monkey experience the
                                   same acceleration each
                                   will fall equal amounts
                                   and the banana misses
                                   the monkey, moving over
                                   his head.
Wrong move!
The zookeeper aims
at the monkey and
shoots the banana.



Since both banana
and monkey
experience the same
acceleration each will
fall equal amounts the   The key to the zookeeper's
banana reaches the       dilemma is to aim directly at
monkey!                  the monkey.

                                SHOOT THE MONKEY
Happy monkey!

More Related Content

Projectile motion horizontal

  • 1. An object launched into space without motive power of its own is called a projectile.
  • 4. a
  • 7. PROJECTILE MOTION CHARACTERISTICS The projectile has: •a constant horizontal velocity and •a vertical velocity that changes uniformly under the influence of gravity.
  • 8. If an object is projected horizontally, its motion can best be described by considering its horizontal and vertical motion separately. In the figure we can see that the vertical velocity and position increase with time as those of a free-falling body. Note that the horizontal distance increases linearly with time, indicating a constant horizontal velocity.
  • 10. Take this basketball shot as an example. Notice the horizontal velocity of the ball. Look at the spacing of the vertical lines which mark the position of the ball every 10th of a second. The spacing is quite consistent, which indicates a constant horizontal velocity.
  • 11. HORIZONTAL MOTION Velocity (vx) is constant Velocity x vx t Distance x vx t Time x t vx
  • 12. VERTICAL MOTION Velocity (vy) increases under the acceleration due to gravity. Velocity voy 0 vy gt Distance 1 2 y gt 2 Time 2y t g
  • 13. RESULTANT VELOCITY The resultant velocity can be found using the Pythagorean theorem. 2 2 vR (vx ) (v y )
  • 14. 3.6 A ball is thrown horizontally with a velocity of 12 m/s. How far has the ball fallen 2 s later? HORIZONTAL VERTICAL vox = 12 m/s voy = 0 m/s t=2s g = 9.8 m/s2 t=2s vox = vx y = ½ gt2 x = vx t = ½ (9.8)(2)2 = 12(2) = 19.6 m = 24 m
  • 15. 3.7 A rifle with a muzzle velocity of 200 m/s is fired with its barrel horizontally at a height of 1.5 m above the ground. a. How long is the bullet in the air? HORIZONTAL VERTICAL vox = 200 m/s voy = 0 m/s y = 1.5 m 1 2 y gt g = 9.8 m/s2 2 2y 2(1.5) t = 0.55 s g 9 .8
  • 16. b. How far away from the rifle does the bullet strike the ground? x = vx t = 200(0.55) = 110 m
  • 17. 3.8 A ball is rolled off the edge of a table 1 m high with a horizontal velocity of 1.8 m/s. With what velocity does it strike the floor? HORIZONTAL VERTICAL vox = 1.8 m/s voy = 0 m/s y=1m g = 9.8 m/s2 2 2 We need to find the resultant velocity: v f vx vy Where: 1 2 vx = vox = 1.8 m/s y gt 2 vy = voy + gt 2y 2(1) t = 0.45 s g 9 .8
  • 18. vy = 0 + 9.8(0.45) = 4.4 m/s vf (1.8) 2 (4.4) 2 = 4.75 m/s
  • 19. THE MONKEY AND THE ZOOKEEPER The monkey spends most of its day hanging from a branch of a tree. The zookeeper feeds the monkey by shooting bananas from a banana cannon to the monkey in the tree. The monkey usually drops from the tree the moment that the banana leaves the muzzle of the cannon. The zookeeper is faced with the dilemma of where to aim the banana cannon in order to feed the monkey. If the monkey lets go of the tree the moment that the banana is fired, then where should he aim the banana cannon?
  • 20. The zookeeper aims above the monkey (perhaps he presumes that gravity will accelerate the banana downward such that it hits the monkey). What would be the path of the banana? Would the banana hit the monkey? Since both banana and monkey experience the same acceleration each will fall equal amounts and the banana misses the monkey, moving over his head.
  • 22. The zookeeper aims at the monkey and shoots the banana. Since both banana and monkey experience the same acceleration each will fall equal amounts the The key to the zookeeper's banana reaches the dilemma is to aim directly at monkey! the monkey. SHOOT THE MONKEY