Term
|
Definition
A scalar is a physical property with magnitude but not direction. Another word for
magnitude is size. Examples of
scalars include
speed, distance, temperature and
wavelength |
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Term
|
Definition
This is a quantity that has both size and direction. Another word we can use for size is called
magnitude. Examples are velocity, force, acceleration and electric current. |
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Term
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Definition
| This is the distance travelled in a particular direction. The unit for distance is the metre. |
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Term
|
Definition
Th
is
is
the speed of an object at a
moment in time. A
cars speedometer gives the driver an
instantaneous speed. |
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Term
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Definition
| A measure of the total distance travelled in a unit time. |
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Term
|
Definition
The velocity of a moving object
is its displacement per unit time |
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Term
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Definition
| The acceleration of an object is its rate of change of velocity |
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Term
|
Definition
The Newton is the unit of force. 1 N is the force which gives a mass of 1 Kg an acceleration
of 1 ms^-2 |
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Term
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Definition
| This is the turning effect due to a couple. It is measured in Newton metres (Nm). |
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Term
|
Definition
The
moment of a force is the
turning effect due to a single force.
It is calculated by
multiplying the force by the perpendicular distance from a given point. The units are
Newton
metres. (Nm) |
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Term
|
Definition
This is the distance travelled
by a vehicle
from seeing the need to stop to applying the
brakes |
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Term
|
Definition
The distance a vehicle travels while decelerating to a stop. This is the distance travelled
after the brakes have been applied. |
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Term
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Definition
| The stopping distance is the thinking distance added to the braking distance. |
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Term
|
Definition
The product (multiplied
together)
of
a
Force and the distance moved in the direction of the
force
gives the work done
by the force. It can also be thought of as the energy converted
from one form into another. The units for work done are Joules. (J) |
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Term
|
Definition
This is the unit of energy. 1 Joule is the work done when a force of 1 N moves its point of
application 1 m in the direction of the force. |
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Term
|
Definition
| Power it the rate at which work is done. It is measured in Watts (W). |
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Term
|
Definition
This is the unit of power. One watt is equal
to one joule per second. 1 W = 1
JS^-1 |
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Term
|
Definition
This is the force per unit cross
-
sectional area. It is measured in Nm
-
2
or Pascals (Pa). |
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Term
|
Definition
This is the extension per unit
length
.
It has no units |
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Term
|
Definition
This is the ratio between stress and strain i.e. the stress divided by the strain. It has the
same unit
s as stress namely
Newton
metres squared
(
Nm
-
2
)
or
Pascal
(Pa) |
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Term
|
Definition
This is the
maximum tensile
(
stretching
)
force that can be applied to an object before it
breaks |
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Term
|
Definition
This means that
t
he object will return to its original shape when the deforming force is
removed. |
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Term
|
Definition
This means that t
he object will not return to its original
shape when the deforming force is
removed,
it becomes permanently deformed |
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