Ch. 6 Flashcards Preview

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Flashcards in Ch. 6 Deck (15):
0

What is speed?

the ratio of the distance an object moves to the amount of time it takes to move

1

how is instantaneous speed different from average speed?

Instantaneous speed- the speed at a certain moment in time
average speed- the speed for an entire trip

2

How do you find the average speed?

V=d/t
(Velocity=distance divided by time)

3

What type of speed does a speedometer on a car show?

Instantaneous speed

4

The slope on a distance-time graph represents __________.

speed

5

Describe a change in velocity.

-A moving object gains speed
-A moving object changes direction
-A moving object slows down

6

A river flows at a velocity of 3 km/h relative to the riverbank A boat moves upstream at a velocity of 15 km/h relative to the river What is the velocity of the boat relative to the riverbank?

12 km/h upstream

7

The rate at which velocity changes is called what?

acceleration

8

Because acceleration is a quantity that has both magnitude and direction, it is a ___________.

vector

9

___________ is the result of increases and decreases in speed.

acceleration

10

Ignoring air resistance, a rock in free fall will have a velocity of what?

39.2

11

Describe constant acceleration.

a steady change in velocities

12

What equation can you use to calculate the acceleration of an object?

A=Vf-Vi/t

13

When the final velocity is ____ than the initial velocity of an object, the acceleration is negative.

less

14

The plotted data points representing acceleration in a distance-time graph form a ______.

curve