1. Cat Scratcher
By: Mrs. Swaim

2. My Cat Scratcher

3. What It Does
My machine makes scratching your cat easier.  You first have your cat walk through the tunnel.  While your cat is in the tunnel you move the handle back and forth to rub you cat.  This solves the problem of having to get a sore arm while brushing your cat for hours.

4. How It Works
My cat scratcher works by using a lever to move a cat brush back and forth.  The lever moves the brush instead of you moving your arm.

5. It’s Simple Machine
My cat scratcher has a lever in it.  The lever works to easily move the brush back in forth without having to move your arm as far as it would have to if you were brushing your cat normally.

6. How It Was Tested
To test my machine I first tested how many Newtons it took to brush a cat with a regular cat brush.  I attached a spring scale to the end of a cat brush and recorded how many Newtons it took to brush the cat.  Next, I attached the spring scale to the end of my lever and recorded how many Newtons it took to move the lever when the cat was under the brush.

7. It Does Work
My cat scratcher does work by the scientific definition of work.  As you can see by my data below, it takes less force to use the machine to scratch a cat than it does to scratch a cat without the machine.  The cat scratcher does work by moving the brush back and forth using less movement by the person.  Below are my results.
Test Number
Without the Machine
With the Machine 1
20 Newtons
8 Newtons 2
23 Newtons
9 Newtons 3
19 Newtons
7 Newtons