Physics 221 Worksheet: Chapter 3,Two Dimensional Motion
1) You drive 4 miles due east and then turn north for 3 miles. Your displacement is:
a) 7 miles.
b) 2 miles.
c) 5 miles.
d) 25 miles.
2) A plane heads due north with an airspeed of 300 km/hr. There is a cross wind from the east at 150 km/hr. The actual direction in which the plane flies is:
a) 30° east of north.
b) 30° west of north.
c) 27° east of north.
d) 27° west of north.
3) In the diagram at the left, the x - component of the vector is given by
a)
A sin q
b) A cos q
c) A tan q
d) A/sin q
e) A/cos q
f) A/tan q
4) A ball thrown horizontally from the top of a building reaches the ground in 5.0 s. If it were thrown with a greater speed it would reach the ground:
a) in less than five seconds and in the same place.
b) in more than five seconds and in the same place.
c) in less than five seconds and closer to the building.
d) in more than five seconds and farther from the building.
e) in exactly five seconds but farther from the building.
f) in exactly five seconds but closer to the building.
5) A ball thrown horizontally from the top of a building reaches the ground in 5.0 s. If it were thrown at the same speed from a taller building it would reach the ground:
a) in less than five seconds and in the same place.
b) in more than five seconds and in the same place.
c) in less than five seconds and closer to the building.
d) in more than five seconds and farther from the building.
e) in exactly five seconds but farther from the building.
f) in exactly five seconds but closer to the building.
6) Which of the following statements is not true for an object thrown horizontally?
a) the horizontal component of the velocity is constant.
b) the horizontal component of the acceleration is zero.
c) the vertical component of the velocity is constant.
d) the vertical component of the acceleration is g.
7) Draw the resultant vector on the diagram.
Ans: 1-c, 2-d, 3-b, 4-e, 5-d, 6-c
Physics 221 Worksheet: Two Dimensional Motion (Part 2)
1) Which of the following is a true statement about vectors?
a) A vector cannot have zero magnitude if any of its components is not zero.
b) The magnitude of a vector can be less than one of its components.
c) If |A| < |B| then each component of A is less than the corresponding component of B.
d) Vectors that lie in the second and third quadrents have negative magnitudes.
2) If you wish to cross a river in the least time you should head:
a) directly across the river
b) slightly upstream
c) slightly downstream
3) A light plane has an airspeed of 40 m/s due north and is flying in a crosswind of 30 m/s. The plane’s speed relative to the ground is:
a) 10 m/s
b) 40 m/s
c) 50 m/s
d) 70 m/s
4) A stone is thrown horizontally from the top of a building at the same instant that a ball is dropped. Which reaches the ground first?
a) the ball
b) the stone
c) both reach the ground at the same time
5) A stone is thrown horizontally from the top of a building at the same instant that a ball is dropped. Which is traveling faster when itreaches the ground?
a) the ball
b) the stone
c) both reach the ground at the same speed
6) A pilot flying horizontally at constant speed drops a package from an airplane. When the package reaches the ground the plane will be: (Ignore air resistance)
a) directly above the package
b) somewhat in front of the package
c) somewhat in back of the package
7) A pilot flying horizontally at constant speed drops a package from an airplane. When the package reaches the ground the plane will be: (Do not ignore air resistance)
a) directly above the package
b) somewhat in front of the package
c) somewhat in back of the package
8) If the acceleration of an object is perpendicular to its velocity, the object must:
a) speed up
b) slow down
c) change direction
9) Which of the following operations does not change a vector?
a) translation parallel to itself
b) rotation
c) multiplication by a constant value
Ans: 1-a, 2-a, 3-c, 4-c, 5-b, 6-a, 7-b, 8-c, 9-a
Physics 221 Worksheet: Chapter 3, Trig Practice
In each figure, calculate x, y, q, and y.
Ans: a) x = 94.3, y = 82.0, q = 49° ; b) x = 46.2, y = 59.1, q = 52o ; c) x = 350, y = 268, q = 50o
d) x = 56.3, q = 56.6o , y = 33.4o; e) x = 52.1, q = 49.9o, y =40.1o ; f) x = 26.8, y = 15.4, q = 55o