Kinematics

Question 1

Kinematics

Answer 1

Motion in one direction

Question 2

The first two important things

Answer 2

1. The object of interest

2. The person describing the object

Question 3

Reference frame

Answer 3

All motion is relative

Question 4

Inertial reference frame

Answer 4

No acceleration

Question 5

Non-inertial reference frame

Answer 5

Acceleration

Question 6

Is there an ideal reference frame?

Answer 6

No, there is no universal reference frame that is not moving.

Question 7

What does “speed is a scalar” mean?

Answer 7

It has a magnitude but no direction.

Question 8

What does “velocity is a vector” mean?

Answer 8

It has a magnitude and a direction.

Question 9

Order of magnitude

Answer 9

Power of 10.

Question 10

What is the physical meaning of the slope of a position vs. time graph?

Answer 10

The object’s velocity.

Question 11

What is the physical meaning of the slope of a velocity vs. time graph?

Answer 11

The object’s acceleration.

Question 12

Velocity =

Answer 12

Displacement/time

∆x/∆t

Question 13

Acceleration =

Answer 13

∆v/∆t

Question 14

Motion

Answer 14

A change in an object’s position relative to a given observer during a certain change in time.

Question 15

Motion is relative

Answer 15

The motion of any object of interest depends on the point of view of the observer.

Question 16

Components of a reference frame

Answer 16

An object of reference
A coordinate system
A clock

Question 17

Time or clock reading t (a scalar quantity)

Answer 17

The reading on a clock or another time measuring instrument.

Question 18

Time interval Δt (a scalar quantity)

Answer 18

The difference of two times.

Question 19

Position x (a scalar quantity)

Answer 19

The location of an object relative to the chosen origin.

Question 20

Displacement ⃗d

Answer 20

A vector drawn from the initial position of an object to its final position. The x-component of the displacement dx is the change in position of the object along the x-axis.

Question 21

Distance d (a scalar quantity)

Answer 21

The magnitude of the displacement and is always positive.

Question 22

Path length l

Answer 22

The length a string laid along the path the object took (total distance).

Question 23

Velocity ⃗v (a vector quantity)

Answer 23

The displacement of an object during a time interval divided by that time interval. The velocity is instantaneous if the time interval is very small (approaches zero) and average if the time interval is longer.

Question 24

Speed v (a scalar quantity)

Answer 24

The magnitude of the velocity.

Question 25

Acceleration ⃗a (a vector quantity)

Answer 25

The change in an object’s velocity ∆v ⃗ during a time interval ∆t divided by the time interval. The acceleration is instantaneous if the time interval is very small (approaches zero) and average if the time interval is longer.

Question 26

Displacement (from velocity graph)

Answer 26

The area between a velocity-versus-time graph line and the time axis.