Power
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Power is ?
The rate at which energy is transformed or the rate at which work is done.
Power is measured as ?
Work per unit of time
Power=?
Work ________ Time
James watt designed a workable steam engine and defined horsepower as a rating of?
550 f•t/s
Horsepower is?
a measurement of power defined as a power rating of 550 ft•lb/s
What is mechanical advantage?
The force or distance advantage you gain by using the machine
Effort force?
The force that you provide by using the machine.
Resistance force?
The force that you and the machine are working against together.
Effort distance?
The distance over, which your effort force acts.
Work input = work output
Effort force X effort distance
The mechanical advantage can be found by?
From a ratio of the resistance force(FR) divided by the effort force(FE)
Mechanical advantage formula?
MA=FR. __________ FE
You can also find the mechanical advantage by?
Dividing the effort distance(DE) by the resistance distance(DR)
There are six kinds of simple machines:
1.) inclined plane. 2.) wedge. 3.) screw. 4.) lever. 5.) wheel. 6.) axle and pulley.
The screw and wedge can be considered as what?
Inclined planes
The wheel, the axle and the pulley can be considered as?
Types of levers
Inclined plane
Is a stationary ramp that is used to trade distance for force
The mechanical advantage of this inclined plane is?
MA=DE __________ DR
A wedge is?
An inclined plane that moves.
A screw is?
An inclined plane that has been wrapped around a cylinder
A lever is?
A bar or board that is free to pivot about a fixed point called a fulcrum
What are three classes of levers?
A first class lever has the fulcrum between the effort force And the resistance force Examples are a seesaw scissors, crowbar, pliers, and a shovel. A second class lever has the effort resistance between the fulcrum and the offer force. Examples are a nutcracker and Twist type jar openers A third class lever has an effort force between the resistance, force, and the fulcrum. Examples are tweezers and fishing rods
And the metric system power is measured by joules per second the unit jewels per second has a name?
The unit jewels per second name is a watt
1000 Watts= 1 kW 1,000,000 Watts= 1 megawatt 746 watts= 1 horsepower 1 kW=1 1/3 horsepower