Chapter 3 Motion in Two Dimensions - Physics-matters.net

NAME: _________________________ PER: _______ DATE: ________
CHAPTER 3
MOTION IN TWO DIMENSIONS
CONCEPTS QUESTIONS
1. An operation that will not change a vector is when it is _________________________
2. A pilot drops a bomb from a plane flying horizontally. When the bomb hits the ground, the
horizontal location of the plane will be _________________________.
3. A projectiles acceleration remains ________________ when in flight near the earth.
4. A single force can be resolved into an _________________________ of components.
5. A projectile is launched at an angle 60 o above the horizontal. Compared to the vertical
component of the initial velocity of the projectile, the vertical component of the projectile’s
velocity when it has reached its maximum height is __________________.
6. An Olympic athlete throws a javelin at four different angles above the horizontal, each
with the same speed: 30 o , 40 o , 60 o , 80 o . The ____________ throws cause the javelin to land
at the same place.
7. A river flows due east at 1.5 m/s. A ship leaves the north shore of
the river and heads due south at 2.0 m/s, as shown to the right. The
vector that best represents the resultant velocity of the ship relative
to the riverbank is_________
8. The acceleration of gravity on the moon is only one-sixth of that on earth. If you
hit a baseball on the moon with the same effort (and at the same speed and angle)
that you would on earth, the ball would land ___________________
9. Ignoring air resistance, the horizontal component of a projectile’s acceleration ____________.
10. A ball is fired vertically upward at 5.0 m/s from a cart moving
horizontally to the right at 2.0 m/s. The vector that best represents
the resultant velocity of the ball when fired is _________

11. For a projectile launched at an angle of 45 o to the horizontal, the vertical speed ____________
on the way up and ______________ on the way down.
12. If several projectiles are fired at the same time, the one that will be in the air the longest is
the one with the __________________________.
13. The vector that represents the resultant of the concurrent vectors A and
B in the diagram to the right is ________
14. If the acceleration of an object always directed perpendicular to its velocity, the ____________.
15. If three vectors add to zero, they must be in the ________________
16. The vector that best represents the resultant of forces F r 1
and F r 2
acting
concurrently on point P is _______
17. An object is thrown into the air and follows the path in the diagram to the
right. The vector that best represents the acceleration of the object at
point A is _______.
18. A projectile is launched at an θ to the horizontal with an initial velocity v. In the absence of
any air resistance the horizontal _____________________
19. Ignoring air resistance, the vertical component of a projectile’s velocity __________________
20. Ignoring air resistance, the horizontal component of a projectile’s ______________________.
21. Two forces act on an object concurrently. The resultant will be greatest when the angle between
the force is ______________

22. A ball rolls down a curved ramp from a table top. The dotted line that
best represents the path of the ball after leaving the ramp is _______
23. A water-gun should be aimed at ____ in order for the water to land
with the greatest horizontal range.
24. The diagram to the right shows a ball projected horizontally with an
initial velocity of 20.0 m/s east, off a cliff 100-m high. During the flight
of the ball, the direction of its acceleration is ________________
25. You hit a tennis ball over the net. When the ball reaches its maximum height, its speed is
_____________________
26. A cannon elevated at an angle of 35 o to the horizontal fires a
cannonball, which travels the path shown in the diagram to the
right. If the angle of elevation of the cannon is decreased from 35 o to
30 o , the _______________ of the ball’s initial velocity will __________
and its ____________________ will ________________
27. An arrow, A is shot horizontally from a bow at a speed of 50 m/s as
shown to the right. A second arrow, B, is dropped from the same height
and at the same as A is fired. Neglecting air friction, compared to the
amount of time A takes to strike the ground, the amount of time B takes
to strike the ground _________________
28. A stone is thrown horizontally from the top of a tower at the same instant that a ball is
dropped vertically. The stone is traveling ____________ when it hits the level ground below.
29. A vector cannot have a zero magnitude if one of its components is ____________
30. If three forces, each having a magnitude of 30N, pull on an object in directions that are 120 o
apart from each other, the resultant force is __________________