Name___________



Study Guide for Exam on Two Dimensional Motion

The exam will consist of 20 multiple choice questions and 3 constructed response questions. (1 of the constructed response questions will pertain to drawing scaled vector diagrams and finding a resultant, one question will pertain to inclined planes, and the other constructed response question will pertain to projectile motion)

You must be able to do the following:

1. Define vectors and scalars. Be able to state examples of vector and scalar quantities.

2. Be able to analyze displacement-time graphs and velocity-time graphs.

a) For example, know that the slope of a displacement-time graph represents the velocity and that the slope of a velocity-time graph represents the acceleration.

b) Recognize that the area under a velocity-time graph represents the distance traveled.

3. Be able to explain the motion of a projectile launched horizontally.

a) Calculate the flight time of a projectile launched horizontally from a given height.

b) Calculate the horizontal distance that a projectile launched horizontally travels.

c) Explain why a bowling ball dropped from rest and a bullet fired horizontally will land at the same time if both have the same initial height.

4. Be able to explain the motion of a projectile launched at an angle.

a) Resolve the initial velocity vector into horizontal and vertical components.

b) Calculate the maximum height reached by a projectile

c) Calculate the total flight time (or hang time) of a projectile launched at an angle.

d) Calculate the range of a projectile launched at an angle.

e) What launch angle will give a projectile its greatest range? What launched angle will give a projectile its maximum height and/or flight time?

5. Be able to explain how the vertical velocity, horizontal velocity, and acceleration of a projectile change as it moves along its parabolic trajectory. (Note: some of these quantities might be constant)

6. Be able to analyze inclined plane

a) Resolve the weight force into its components, FgsinƟ and FgcosƟ. Know what these components represent

b) Be able to draw a freebody diagram of an object on an incline, identifying the direction of the weight force, normal force, and friction

Constructed Response Sample Questions

I. Projectile Motion

1) A 2 kg ball is thrown horizontally at 20 m/s off of a cliff that is 125 m high.

a) How long does it take the ball to hit the ground?

b) How far does the ball land from the base of the cliff?

2) Person A kicks a football with a velocity of 15 m/s at an angle of 20 degrees with respect to the horizontal. Person B kicks a football with a velocity of 15 m/s at an angle of 60 degrees with respect to the horizontal. ( No calculations necessary)

a) Compare the maximum heights reached by each football.

b) Compare the range of each football.

c) Compare the flight times of each football.

3) Sample Question: A projectile is launched at an angle of 60 degrees with an initial velocity of 30 m/s.

a) If the projectile is launched at an angle of 75 degrees with the same velocity, will it reach a higher or lower altitude than when launched at a 60 degree angle?

b) If the projectile is launched at an angle of 75 degrees with the same velocity, will it have a longer or shorter range than when launched at an angle of 60 degrees?

II. Inclined Planes

1) A 10 kg crate is at rest on a 30 degree inclined plane. Draw a freebody diagram showing the weight force, normal force, and friction force acting on the 10 kg mass.

[pic]

III. Vector Drawings

1. A treasure map gives the following directions to buried treasure: “Start at the old oak tree, walk due north for 530 meters, then due east for 130 meters. Dig”.

a) Determine a scale that you can use to graphically represent the displacement vectors.

b) Draw the resultant displacement vector from the old oak tree.

c) Determine the magnitude of the resultant displacement vector.

d) Determine the angle between the resultant displacement vector and the east axis.

2. Forces with magnitudes of 180 N and 120 N act on a hook. The 180 N force acts northward and the 120 N force acts to the east.

[pic]

3. A plane is flying at 500 meters per second at 37 degrees south of east. It flies into a jet stream, whose velocity is 100 meters per second east.

a) Determine a scale that you can use to graphically represent the velocity vectors.

b) Draw the resultant velocity vector.

c) Determine the magnitude of the resultant velocity .

d) Determine the angle between the resultant velocity vector and the east axis.

4. Two concurrent forces act on an object as shown below

[pic]

a) Determine the scale that was used to represent the force vectors.

b) Draw the resultant force vector.

c) Determine the magnitude of the resultant force.

d) Determine the angle between the resultant force and the east axis.

-----------------------

a)./ikûþ - 2 y   ÷ 2>Ý

2

4

y

Î

!

2

¯

ó

2

@

u

Ê

2

“

2]®¯l|~€‚„†íÛʼʼ¼¼ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊ®®Ÿ®?®®ÊÊÊ®h:"QCJOJPJQJaJ#hd`hd`CJH*[?]OJPJQJaJhd`CJH*[?]OJPJQJaJhd`CJOJPJQJaJh

-ïCJOJPJQJaJ hd`hd`CJOJPJQJaJ#hd`hpT Determine the scale that was used to graphically represent the force vectors.

b) Draw the resultant force or net force.

c) Determine the magnitude of the resultant force vector.

d) Determine the angle between the resultant force vector and the east axis.

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download