Q: A runner completes a 100 m sprint in 12 seconds. What is the runner's average velocity?

$$\frac{100}{12} = 8.33\ \text{m/s}$$

Q: If a particle moves from $$x_1 = 10$$\ \text{m}$$ to x_2$ = 40\ \text{m} in$$ $$t_2$$ - $$t_1 = 3$$\ \text{s}$$, what is its average velocity?

$$\frac{40 - 10}{3} = 10\ \text{m/s}$$

Q: A dragster accelerates along a straight track. If its position changes from $$x_1 = 0$$\ \text{m}$$ to x_2$ = 150\ \text{m} in$$ $$\Delta t = 2\ \text{s}$$, what is its average velocity?

$$\frac{150}{2} = 75\ \text{m/s}$$

Q: A runner starts at $$x = 0\ \text{m}$$ and finishes at $$x = 50\ \text{m} in$$ $$t = 10\ \text{s}. $$What is the average velocity?

$$\frac{50}{10} = 5\ \text{m/s}$$

Q: A swimmer completes a 50 m race in 20 seconds. What is her average velocity?

$$\frac{50}{20} = 2.5\ \text{m/s}$$

Q: If a particle moves from $$x_1 = -20$$\ \text{m}$$ to x_2$ = -10\ \text{m} in$$ $$t_2$$ - $$t_1 = 2$$\ \text{s}$$, what is its average velocity?

$$\frac{-10 - (-20)}{2} = 5\ \text{m/s}$$

Question 1

A runner completes a 100 m sprint in 12 seconds. What is the runner's average velocity?

Accepted Answer

$$\frac{100}{12} = 8.33\ 	ext{m/s}$$

Question 2

Which statement best describes the difference between average speed and average velocity?

Accepted Answer

Average speed is total distance divided by time, while average velocity is displacement divided by time.

Question 3

A swimmer completes a 50 m race in 25 seconds. If she returns to her starting point immediately, what is her average velocity for the entire trip?

Accepted Answer

$$0\ 	ext{m/s}$$

Question 4

Given the position-time graph, what does the slope of the tangent at any point represent?

Accepted Answer

The instantaneous velocity at that point.

Question 5

If a particle moves from $$x_1 = 10$$\ 	ext{m}$$ to x_2$ = 40\ 	ext{m} in$$ $$t_2$$ - $$t_1 = 3$$\ 	ext{s}$$, what is its average velocity?

Accepted Answer

$$\frac{40 - 10}{3} = 10\ 	ext{m/s}$$

Question 6

A dragster accelerates along a straight track. If its position changes from $$x_1 = 0$$\ 	ext{m}$$ to x_2$ = 150\ 	ext{m} in$$ $$\Delta t = 2\ 	ext{s}$$, what is its average velocity?

Accepted Answer

$$\frac{150}{2} = 75\ 	ext{m/s}$$

Question 7

Which of the following best describes the instantaneous velocity $$v_x$$?

Accepted Answer

$$v_x = \frac{dx}{dt}$$

Question 8

On a position-time graph, what does a zero slope indicate about the particle's motion?

Accepted Answer

The particle is momentarily at rest.

Question 9

A particle moves along the x-axis. If its x-coordinate is negative and decreasing, what is the sign of its velocity?

Accepted Answer

Negative

Question 10

A runner starts at $$x = 0\ 	ext{m}$$ and finishes at $$x = 50\ 	ext{m} in$$ $$t = 10\ 	ext{s}. $$What is the average velocity?

Accepted Answer

$$\frac{50}{10} = 5\ 	ext{m/s}$$

Question 11

If a particle's position-time graph has a negative slope, what does this indicate about its velocity?

Accepted Answer

The velocity is negative.

Question 12

A swimmer completes a 50 m race in 20 seconds. What is her average velocity?

Accepted Answer

$$\frac{50}{20} = 2.5\ 	ext{m/s}$$

Question 13

If a particle moves from $$x_1 = -20$$\ 	ext{m}$$ to x_2$ = -10\ 	ext{m} in$$ $$t_2$$ - $$t_1 = 2$$\ 	ext{s}$$, what is its average velocity?

Accepted Answer

$$\frac{-10 - (-20)}{2} = 5\ 	ext{m/s}$$

Question 14

Which scenario best illustrates the concept of instantaneous velocity?

Accepted Answer

The speedometer reading of a car at a specific instant.

Question 15

A particle moves along the x-axis. If its x-coordinate is positive and decreasing, what is the sign of its velocity?

Accepted Answer

Negative

Question 16

On a position-time graph, what does a positive slope indicate about the particle's motion?

Accepted Answer

The particle is moving in the positive x-direction.

Question 17

A dragster moves from $$x_1 = 0$$\ 	ext{m}$$ to x_2$ = 160\ 	ext{m} in$$ $$t_2$$ - $$t_1 = 4$$\ 	ext{s}$$. What is its average velocity?

Accepted Answer

$$\frac{160}{4} = 40\ 	ext{m/s}$$

Question 18

If a particle's position-time graph has a tangent with zero slope at point C, what is the particle's velocity at that instant?

Accepted Answer

$$v_x = 0$$

Question 19

A particle moves from $$x_1 = 100$$\ 	ext{m}$$ to x_2$ = 55\ 	ext{m} in$$ $$t_2$$ - $$t_1 = 1$$\ 	ext{s}$$. What is its average velocity?

Accepted Answer

$$\frac{55 - 100}{1} = -45\ 	ext{m/s}$$

Kinematics: Motion Along a Straight Line – Displacement, Velocity, and Graphical Analysis

Guida di studio - Domande di pratica

Study guide - Flashcard