1.2 Dynamics Flashcards

0
Q

Give a few examples of forces…

A

Weight, friction, thrust, lift, magnetic

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

What does force change?

A

Speed, direction and shape of an object.

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

What is used to measure force?

A

A newton balance. 1N = 1cm extension

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

What is weight?

A

The Earth’s pull on an object.

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

Is weight a scalar or vector quantity?

A

vector

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

What are the symbol and unit for weight?

A

W and newtons (N)

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

What is the equation for weight?

A

W=mg

weight equal mass times gravitational field strength

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

What is mass?

A

The measure of matter within an object.

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

Is mass a scalar or vector quantity?

A

scalar

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

What are the unit and symbol for mass?

A

m and kilograms (kg)

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

What is gravitational field strength?

A

The weight per unit mass.

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

What are the symbol and unit of gravitational field strength?

A

g and newtons per kilogram (N/kg)

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

What is the value of gravitational field strength on Earth?

A

10N/kg

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

What is the force of friction?

A

Opposes the motion of the object.

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

In what situations is friction wanted?

A

sitting, driving, writing, bikes, walking

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

In what situations is friction unwanted?

A

racing cars, fast cars

16
Q

What can be done to reduce friction?

A

lubrication, streamlining, ball bearings

17
Q

What is Newton’s 1st Law of Motion?

A

An object will continue to travel at a constant velocity unless acted on by an unbalanced force.

18
Q

What are balanced forces?

A

Forces that are opposite in direction but equal in magnitude.

19
Q

Is force a vector or scalar quantity?

20
Q

What is Newton’s 2nd Law of Motion?

A

Acceleration of an object is directly proportional to the magnitude of unbalanced force acting and inversely proportional to the mass.

21
Q

What is the equation linking force, mass and acceleration?

A

F=ma

force (F) equals mass (m) times acceleration (a)

22
Q

What is the newton and it’s symbol?

A

The force needed to accelerate 1kg at 1m/s. (N)

23
Q

What is the resultant force?

A

The resulting force acting on an object when balanced forces have been subtracted.

24
What is the method of calculating resultant force? (3 steps)
1) free body diagram 2) tip to tail 3) calculate resultant
25
Explain the equivalence of acceleration due to gravity and gravitational field strength...
F=W F=ma W=mg ma=mg a=g
26
Which objects does acceleration due to gravity affect and what is its symbol?
objects in freefall accelerate at a rate equal to the acceleration due to gravity. (a)
27
What is a projectile?
An object traveling horizontally and vertically at the same time.
28
Explain the curved path of projectiles in terms of the force of gravity...
Vertically the object accelerates due to gravity and the combined result of horizontal and vertical motion is a curved path.