Physics 151 Week 6 Day 2

Topics– Trigonometry Review– Vector Components– Vector magnitude and direction

General Motion Model

Slide 2-4

Constant Acceleration and Constant Velocity Model

Trigonometry and Vector Component Review

Component Vectors and Components

Slide 3-22

What are the x- and y-components of these vectors?

A. 3, 2B. 2, 3C. 3, 2D. 2, 3E. 3, 2

Checking Understanding

Slide 3-23

What are the x- and y-components of these vectors?

Answer

Slide 3-24

A. 3, 2B. 2, 3C. 3, 2D. 2, 3E. 3, 2

What are the x- and y-components of these vectors?

A. 3, 1B. 3, 4C. 3, 3D. 4, 3E. 3, 4

Checking Understanding

Slide 3-25

What are the x- and y-components of these vectors?

Answer

Slide 3-26

A. 3, 1B. 3, 4C. 3, 3D. 4, 3E. 3, 4

The following vectors have length 4.0 units.What are the x- and y-components of these vectors?

A. 3.5, 2.0B. 2.0, 3.5C. 3.5, 2.0D. 2.0, 3.5E. 3.5, 2.0

Checking Understanding

Slide 3-29

The following vectors have length 4.0 units.What are the x- and y-components of these vectors?

Answer

Slide 3-30

A. 3.5, 2.0B. 2.0, 3.5C. 3.5, 2.0D. 2.0, 3.5E. 3.5, 2.0

A. tan–1(Cy /Cx)

B. tan–1(Cx /|Cy|)

C. tan–1(Cy /|Cx|)D. tan–1(Cx /Cy)

E. tan–1(|Cx |/|Cy|)

Angle φ that specifies the direction of is given by

_C

A. tan–1(Cy /Cx)

B. tan–1(Cx /|Cy|)

C. tan–1(Cy /|Cx|)D. tan–1(Cx /Cy)

E. tan–1(|Cx |/|Cy|)

Angle φ that specifies the direction of is given by

_C

The following vectors have length 4.0 units.What are the x- and y-components of these vectors?

A. 3.5, 2.0B. 2.0, 3.5C. 3.5, 2.0D. 2.0, 3.5E. 3.5, 2.0

Checking Understanding

Slide 3-27

The following vectors have length 4.0 units.What are the x- and y-components of these vectors?

Answer

Slide 3-28

A. 3.5, 2.0B. 2.0, 3.5C. 3.5, 2.0D. 2.0, 3.5E. 3.5, 2.0

Vector Components

Vector Components

Problem 2.64

A 200 kg weather rocket is loaded with 100 kg  of fuel and fired straight up. It accelerates upward at 30.0 m/s2 for 30.0 s, then runs out of fuel. Ignore any air resistance effects.

A. What is the rocket’s maximum altitude?

B. How long is the rocket in the air?

C. Draw a (quantitative) velocity-versus-time graph for the rocket from liftoff until it hits the ground.

Pictorial Diagram Example 2

Exam Tips

• Instantaneous velocity

• Area under the graph

• Algebra in symbols

• Givens Required

• Complete explanations

• Use homework to practice good solutions