Question 1

A ball is tossed straight up in the air. At its very highest point, what is the direction of its acceleration vector?

Accepted Answer

It points down.

Question 2

Which of the following best describes the velocity vectors in a motion diagram for a car that is accelerating up a hill from rest?

Accepted Answer

The velocity vectors are getting longer.

Question 3

Given the equation for average velocity $$\frac{\Delta r}{\Delta t}$$, what does $$\Delta r$$ represent in the context of motion diagrams?

Accepted Answer

The displacement vector.

Question 4

A student walks to school and her position vs. time graph shows a plateau for 10 minutes at $$x = -20 km. $$What does this indicate about her motion during that interval?

Accepted Answer

She is stopped.

Question 5

In a motion diagram, how do you represent acceleration vectors?

Accepted Answer

By connecting each two velocity vectors.

Question 6

A cheetah accelerates quickly, runs at top speed for a short distance, and then slows down. Which of the following best describes the acceleration vector during the slowing down phase?

Accepted Answer

It points in the opposite direction to the velocity vector.

Question 7

If an object is moving to the right and speeding up, what can you say about the signs of its velocity $$v$$ and acceleration $$a$$?

Accepted Answer

Both $$v \u003e 0$$ and $$a \u003e 0.$$

Question 8

A rocket sled accelerates at $$50\ \mathrm{m/s^2$}$$ for $$5.0\ \mathrm{s}$$, then coasts for $$3.0\ \mathrm{s}$$ with zero acceleration. What is the total time of motion?

Accepted Answer

$$8.0\ \mathrm{s}$$

Question 9

Which of the following is true about acceleration in one-dimensional motion when the object is slowing down?

Accepted Answer

The acceleration and velocity vectors have opposite signs.

Question 10

Convert $$2\ \mathrm{ft} to $$meters using the conversion $$1\ \mathrm{in} = 0.0254\ \mathrm{m}$$ and $$1\ \mathrm{ft} = 12\ \mathrm{in}. $$What is the result?

Accepted Answer

$$0.6096\ \mathrm{m}$$

Question 11

A position vs. time graph for a student walking to school shows a curve that is not a straight line. What does this indicate about the student's motion?

Accepted Answer

The student is accelerating.

Question 12

Which SI unit is used for acceleration?

Accepted Answer

$$\mathrm{m/s^2$}$$

Question 13

A motion diagram shows equally spaced dots with velocity vectors of equal length. What does this indicate about the object's motion?

Accepted Answer

The object is moving at constant velocity.

Question 14

If a particle is slowing down and its position $$x is $$positive, which of the following is true about the sign of its velocity $$v$$?

Accepted Answer

$$v \u003c 0$$

Question 15

Which of the following is NOT a correct step when drawing a motion diagram?

Accepted Answer

Draw acceleration vectors connecting each position dot.

Question 16

A car moves to the left of the origin and stops for 10 minutes at $$x = -20 km. $$What is the sign of its position during this interval?

Accepted Answer

Negative

Question 17

Which representation is most useful for quickly conveying a lot of information about an object's motion over time?

Accepted Answer

A graph

Question 18

A rocket sled starts from rest and accelerates at $$50\ \mathrm{m/s^2$}$$ for $$5.0\ \mathrm{s}. $$What is its velocity at the end of the acceleration phase?

Accepted Answer

$$250\ \mathrm{m/s}$$

Question 19

Which of the following is the correct SI unit for force?

Accepted Answer

$$\mathrm{N}$$

Motion Diagrams, Velocity, and Acceleration in Kinematics

Guida di studio - Domande di pratica

Study guide - Flashcard