Pulley
·
The movable decreases the amount of work needed
by half. Moves with the load. As it moves, the distance of the string increases
by double the amount of the object being moved.
Force through a distance equals
work (work = force x distance). It takes two components to make work. Energy
can be exerted, however if nothing moves, then work has not been done. Simple
machines help work.
Lever
·
A lever needs a load and a fulcrum to work.
·
They change the direction of the force. They do
not really give an advantage in terms of exerting less force, however the
change in distance is an advantage.
·
A first class lever is similar to a seesaw that
would be found on a playground or a walnut cracker. You push down on a first
class. The fulcrum is in the middle.
·
A
second-class lever is like a wheel barrel. The load is at the bottom and we
lift it from the end. The wheel is the fulcrum. It is at the end.
·
A third class lever, the work is applied to the
middle. The fulcrum is at the end and the load is at the opposite end. This is
similar to a stapler or your arm or a spoon. The load is being lifted up.
No comments:
Post a Comment