P5 Distance, Displacement, Speed and Velocity (page 207) Flashcards

1
Q

Distance is what?

A

Scalar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Displacement is a what?

A

Vector

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is meant by Distance?

A

just how far an object has moved. It’s a scaler quantity (p.201) so it doesnt involve direction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is meant by Displacement is a vector quantity?

A

It measures the distance and dirction in a straigh line from an object’s starting point to its finishing point.

e.g. the plane flew 5 metres north. The direction could be relative to a point, e.g. towards the school, or a bearing (a three-didget angle from north, e.g. 035°).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

If you walk 5 m north, then 5 m south, what would your displacement be? and what wold the distance travelled by?

A

0m m but the distance travelled is 10 m

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Speed and Velocity both measure what?

A

how fast you’re going, but speed is a scalar and velocity is a vector.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Explain what speed is?

A

how fast you’re going (e.g. 30 mph or 20 m/s) with no regard to the direction.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Explain what Velocity is?

A

Speed in a given direction, e.g. 30 mph north or 20 m/s, 060°

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Explain what speed and velocity means?

A

It means you can have objects travelling at a constant speed with a changing velocity. This happens withn the object is changing direction whilst staying at the same speed.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

If an object is moving in a circle at a constant speed and has a constantly changing velocity, what do this mean?

A

the direction is always changing (e.g. a car going round a roundabout)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

If you want to measure the speed of an object that’s moving with a constant speed, how do you do this?

A

you should time how long it takes the object to travel a certain distance, e.g. using a ruler and a stopwatch. You can then calculate the objects speed from your measurements using this formula:

s = vt

distance travelled (m) = speed (m/s) x time (s)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Objects rarely travel at a constant speed, give some examples and explain why?

A

e.g. when you walk, run or travel in a car, your speed is always changing.

for these cases, the formular gives the average (mean) speed during that time.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Whilst every person, train or car etc is different there is usually a typical speed that each object travels at (remember these typical speeds for everyday objects), what are the speeds for the following:

A person walking
A person running
A person cycling
A car
A train
A plane

A

A person walking 1.5 m/s
A person running 3 m/s
A person cycling 6 m/x
A car 25 m/s
A train 30 m/s
A plane 250 m/s

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Lots of different things can affect the speed something travels at, give some examples?

A

the speed at which a person ccan walk, run or cycle depends on their fitness, there age, the distance travelled and the terrain (what kind of land they’re moving over, e.g. roads, fields) as well as many other factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Its not only the speed of objects that varies, what else can varie?

A

the seed of sound (330 m/s in air) changes depending on what the sound waves are travelling through, and the speed of wind is affected by many factors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What can wind speed be affected by?

A

things like temperature, atmospheric pressure and if there are any large buildings or structures nearby (e.g. forests reduce the speed of the air travelling through them).

17
Q

A sprinter runs 200 m in 25 s. Calculate his speed (3 marks)

A

s = vt so v = s ÷ 1 (1 mark)
= 200 ÷ 25 (1mark) = 8 m/s (1 mark)

18
Q

Marie walks her dog after school. She takes a route of 1500 m that starts at and returns to her house.

State a) the distance she travels
b) her displacement

(2 marks)

A

a) Distance travelled = 1500 m (1 mark).
b) Marie’s journey ends at the same position as it started, so the displacement is 0 m (1 mark).