Intro To Forces

Question 1

4 words to describe force

Answer 1

Contact
Body
Concentrated
Distributed

Question 2

Contact? To

Answer 2

Direct physical force

Question 3

Body?

Answer 3

Applied by remote action

Eg: Gravity

Question 4

All contact forces are?

Answer 4

Distributed force

Question 5

Unless?

Answer 5

Area is small in comparison to other dimensions

Question 6

Then it is?

Answer 6

Concentrated force

Question 7

Distance v Displacement?

Answer 7

Ground covered

How far away B is from A

Question 8

Newtons 1st law?

Answer 8

Remains at rest unless acted upon by unbalanced force

Question 9

Equation for body in equilibrium?

Answer 9

Sum of vector F = 0

Question 10

Newtons 2nd law?

Answer 10

Acceleration of a particle is proportional to resultant F

Question 11

Equation

Vector F =

Answer 11

ma

Question 12

Equation

Vector W =

Answer 12

mg

Question 13

Newtons 3rd Law?

Answer 13

For every action , there is an equal and opposite reaction

Equal magnitude
Opp in direction
Collinear

Question 14

Equation

F(bar) B on A =

Answer 14

• F(bar) A on B

Question 15

Compression?

Answer 15

Pushing on body

Question 16

Tension?

Answer 16

Pulling on body

Question 17

F = ma

Units?

Answer 17

Kg x ms^-2

= Newtons

Question 18

Gravity?

Answer 18

Mutual attraction of 2 bodies to each other

Question 19

From the?

Answer 19

Centre of the body

Question 20

Force equation for Attraction of 2 bodies?

Answer 20

F=Gm1m2
———-
r^2

Question 21

Gravitational constant?

Answer 21

6.673 x 10^-11 m3 kg-1 s-2

Question 22

Force(gravity) on earth?

Answer 22

F= m x GM
—-
r2

Question 23

Simplified to?

Answer 23

F= m x 9.81

= mg

Question 24

Vector Addition is?

Answer 24

Commutative

Question 25

4 things forces have?

Answer 25

Magnitude
Direction
Line of action
Point of application

Question 26

If forces are concurrent, they?

Answer 26

Act on same point of application

Question 27

If forces are concurrent at a point?

Answer 27

Their lines intersect at that point

Question 28

Sine rule?

Answer 28

sinA = sinB = sinC
—– —— —–
a b c

Question 29

Cosine rule?

Answer 29

a2 = b2 + c2 - 2bc cosA

Question 30

Rectangular components?
Fx=
Fy=

Answer 30

Fx= Fcos θ
Fy= Fsin θ

Question 31

Mechanics is the study of?

Answer 31

Forces on objects

Question 32

Angle is measured?

Answer 32

Anti clockwise from x axis

Question 33

EQUATIONS:

FRx =

Answer 33

FAx + FBx + FCx

Question 34

EQUATIONS:

FRy =

Answer 34

FAy + FBy + FCy

Question 35

EQUATIONS:

FR2 =

Answer 35

F2Rx + F2Ry

Question 36

EQUATIONS:

tanθ =

Answer 36

FRx