Section 4-1
The unit we use to talk about work.
What is joule?
This is a device with which you can do work in a way that is easier or more effective.
What is a machine?
These connect muscles to bones.
What are tendons?
Calculate the work done by a 47 N force pushing a pencil 0.26 m.
What is 12.22 J?
The formula for work.
What is:
work = force x distance (w = f * d)
The type of force exerted by a machine.
What is output force?
An incisor is an example of this simple machine.
What is a wedge?
If a small motor does 520 J of work to move a toy car 260 m, what force does it exert?
What is 2 N?
In order for you to do work on an object, something must do this.
What is: move the object some distance in the same direction as the force?
The force you exert on a machine.
What is the input force?
A ________ is a grooved wheel with a rope wrapped around it.
pulley
In the arm, your elbow is the ____________________, the ___________________ lifts your arm, and the biceps provide the _______________________
What are the fulcrum, output force, and input force (in that order)?
How much work is it to lift a sack of potatoes vertically 6.5 m if the input force is 73 N?
What is 474.5 J?
A dog uses 4 N of force to move his dog dish 3 meters. A cat uses 5 N of force to move her cat dish 2 meters. This pet does more work.
What is the dog?
True/False: The mechanical advantage is the output force multiplied by the input force.
What is false?
The pivot point of a lever.
What is the fulcrum?
In the head, the joint at the top of your neck is the ________________, the muscles in the back of your neck are the ___________________, and the _____________________ is used to tilt your head back.
What are fulcrum, input force, and output force (in that order)?
A force of 250 N is applied to the rope on a pulley system. The box being lifted is 1250 N. What is the mechanical advantage?
What is 5?
A jeep pulled a car 13 meters out of a mud pit using 33 N of force. Calculate the amount of work being done.
What is 429 joules?
The comparison of the output and input of a machine, expressed as a percent, is this.
What is efficiency?
A device with toothed wheels that fit into one another.
What is a system of gears?
At your head and neck, the muscles in the back of your neck provide the _____________________, the joint at the top of your neck is the ____________________, and the tilting of your head is done by the ____________________.
What are the input force, fulcrum, and output force (in that order)?
To open a bottle of soda, a force of 55 N is applied to the bottle opener. If the bottle opener applies a force of 675 N to the cap, what is the mechanical advantage of the bottle opener?
What is 12.27?