Relativity Lite

6 | Relativity Lite 3. Now trace the square onto a thin sheet of paper (or cut out a square of this size) and rotate the square around the lower left-hand corner until the lower right-hand cor- ner of the square just touches the right-hand edge of the rectangle, approximated by the sequence of three rotated green squares shown in figure 3. c τ c t v t c t Figure 3. The sequence of fours steps described in the text in full. The red rectangle has a width that represents the distance the spaceship travels (6 cm) in an extremely short time compared to the distance light travels, the width of the full 10 cm square, if v is 3 5 6 10 = of the speed of light. If v had equaled c , these widths would have been equal. The sequence of three rotated green squares are stop-motion animation versions of the smooth rotation of the square by the reader. The blue arrows indicate the height measurement asked of the reader. 4. Tape the square in place and measure the distance from the lower right-hand cor- ner of the rotated square to the lower right-hand corner of the rectangle. For the present example, this length is 8 cm, shown as blue in figure 3. Divide 10 cm by this length to get the value of the time-dilation factor. In the present example, this ratio is 5 4 , or 1.25.