Work
a force applied through a distance.
What is work?
A device that changes the direction of the force or increases the motion from work.
What is a machine?
the ratio of output to input work forces of a machine
What is mechanical advantage?
the ratio of output work to input work of a machine.
What is efficiency?
What are three ways machines make work easier?
Changing distance, changing force or changing direction
the equation to calculate force.
What is W = F x d
Power is measured in
Watts
the equation to calculate mechanical advantage
What is output force/input force
the formula for calculating efficiency of a machine
What is (output work/input work) x 100
Is kicking a ball an example of work
Yes the ball moves because you kicked it.
the units for work, a newton-meter
What is a Joule.
The force you apply to the object is the
input force
What is the mechanical advantage of a machine that has an output force of 500 N from an input force of 100 N.
What is 5.
calculate the efficiency of a machine that does 200 J of work from an input of 500 J.
What is 40%.
What distance is an elephant on roller skates pushed if 6,000 J of work was done using 3,000 N of force?
What is 2 m?
A box is pushed across the floor 20 m using 15 N of force. What is the work done on the box?
What is 300 J
The force the machine produces is the
output force
What is the mechanical advantage of a machine that neets 15 N for force to output 300 N of force.
What is 20.
What is an ideal machine?
A machine that is 100% efficient.
Work equals force times
distance
Work is measured in
joules
Why are machines never 100% efficient
They must overcome friction
If a machine changes only the distance what is the mechanical advantage?
It is 1.
If you pick up a backpack and carry it are you doing work?
only when you pick it up not when you are carrying it.