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Flashcards in Dynamics Deck (28):
1

SUVAT without s

v=u+at

2

SUVAT without t

V2=u2+2as

3

SUVAT without a

S=0.5*(u+v)*t

4

SUVAT without u

s=vt-0.5*a*t2

5

SUVAT without v

s=ut+0.5*a*t2

6

Moment of interia

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(1/3)*m*l2

7

Moment of interia

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(1/12)*m*l2

8

What is the equation for normal accleration?

an2r

9

What is the equation for tangentual accleration?

at=αr

10

If you have an object rotating about a piviot, how do you find the normal force in the piviot? (Force pushing into the pivot)

ΣFn =m*ω2*rg

rg is the radius of the centre of gravity

11

If you have an object rotating about a fixed piviot, how do you find the tangentual reaction force in the piviot?

ΣFt = mαrg

12

What is the moment of interia of a disk through the centre?

0.5mr2

13

Relative motion analysis accleration equation

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14

When two gears are meshed together, what can you say about the normal and tangentual accleration?

The velocity and the tangential components of acceleration will be the same, However, the normal components of acceleration will not be the same.

15

Relative motion analysis velocity equation

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16

What is a useful expression for angular accleration?

α=ω*(dω/dθ)

17

In absolute motion analysis, what are useful equations relating the linear speed of a point to the rotational speed of the object?

dx/dt= dx/dθ *ω

dv/dt=dv/dθ * ω

18

What is the velocity equation for relative motion analysis?

Vb=Va+ω X rb/a

X is cross product.

rb/a is how to get to b from a

19

What is the definition of the centre of zero velocity?

To locate the IC, we can use the fact that the velocity of a point on a body is always perpendicular to the relative position vector from the IC to the point

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20

What are the three ways to find the IC?

First, consider the case when velocity va of a point A on the body and the angular velocity ω of the body are known In this case, the IC is located along the line drawn perpendicular to va at A, a distance r = va /ω from A

A second case is when the lines of action of two non-parallel velocities, va and vb , are known. First, construct line segments from A and B perpendicular to va and vb . The point of intersection of these two line segments locates the IC of the body.

 

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21

What is the relative motion analysis accleration equation?

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22

What is the coriolis accleration?

2ΩX(VB/A)xyz

23

What do these terms mean?

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24

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25

What is the equation for moment of interia?

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26

What is the parallel axis theorem?

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27

What is the radius of gyration?

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28

What is a useful equation?

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