Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
Powered is measured in what unit?
|
watt
|
|
The metric unit for work is
|
Joule
|
|
The unit used for force is?
|
newton
|
|
The force of an object that has traveled a distance is the definition of what?
|
work
|
|
The ratio of output force to input force of a simple machine is called?
|
mechanical advantage
|
|
work output=work input is used to describe what type of machine?
|
simple
|
|
A bicycle is an example of what type of machine?
|
complex
|
|
Work divided by the time that it took the object to do work is called?
|
power
|
|
Mr. Webster and I both stand in front of a rope/pulley system. He wants to use three ropes on his pulley and I want to use six to pull up 200N. What has more mechanical advantage?
|
Phillips
|
|
Who uses more force?
|
Webster
|
|
Who has to pull more rope?
|
Phillips
|
|
Who does more work?
|
same
****work output=work input |
|
The fixed point on a lever is called?
|
fulcrum
|
|
When a screw driver turns a screw, the forces do what together?
|
multiply
|
|
what are examples of simple machines?
|
screw, rope/pulley, gears, lever
|
|
Circumference/lead is the equation to find mechanical advantage of?
|
screw
**take the circumference of the screw divided by the distance the screw was turned. |
|
Joann, who has a force of 45 newtons, climbed 3 meter up a ladder to rescue her cat from a tree. How much work against gravity did she do?
|
135J
*work=force x distance |
|
A machine does 1,500 J of work in 30 seconds. What is the power of this machine?
|
50watts
*power = work/time |
|
Suppose a force of 100 newtons is used to push an object a distance of 5 meters in 15 seconds. Find the amount of power done.
|
33.3 watts
*power = work/time |
|
A machine uses an input force of 200 newtons to produce an output force of 80 newtons. What is the mechancial advantage?
|
.4
MA= force output/force input |
|
How much work is done to carry a 20 newton book across a 5 meter room?
|
0
*no work is done in carrying an object. |
|
How much work is done to a 40 newton box that is lifted 8 meters?
|
320 Joules
*work= forcex distance |
|
A 50 Kilogram bicycle racer climbs a 250 meter hill. How much work has he/she done?
|
122,500Joules
*work=mgh |
|
A 60 tooth gear is connected to a 24 tooth gear. If the smaller gear turns ten times, how many times does the larger gear make?
|
4 turns
To/Ti=Ni/No |
|
What is the gear ratio if the input gear has 24 teeth and the output gear has 36 teeth?
|
2:3
input:output |
|
A machine puts off 250 watts of power for every 1250 watts put into it. The efficiency is?
|
20%
*250watts/250wattsx 100=20% |