Force and motion
Force and Motion
Systems
With a little help, students should recognize that the inputs to a video game are through the controls. The actions might include pushing buttons, moving a joystick or turning a trackball. The outputs are the sound effects and motions of figures on a screen. Wii systems often have a wider range of inputs, such as dancing, playing a musical instrument or using fitness equipment. The input to a scissors is moving the handles, and the output is the motion of the blades, or the cutting of the paper. The input to a telephone used to be either pushing buttons (dialing) or talking, and the output was sound, but current phones often include cameras, video games, the Internet, etc. In a mechanical pencil sharpener, the input was turning the crank; electric pencil sharpeners are activated by simply inserting the pencil. Both have the same output: sharpening the pencil. Students are likely to come up with other examples, such as the computer, whose input includes the motion of the mouse. The input to a pop-up mechanism is the opening and closing of the book. The output is the motion of the pop-up piece itself. These relationships are expressed in the diagram below: