Mission CG1 Speed and Velocity
Hold down the T key for 3 seconds to activate the audio accessibility mode, at which point you can click the K key to pause and resume audio. Useful for the Check Your Understanding and See Answers.

Four objects move in circles at different speeds. The radius and the period are listed below. Rank these four objects in increasing order of their speed, beginning with the slowest. List the four letters with no spaces or commas between letters.

The speed of a moving object refers to how fast the object is moving. It is the distance traveled per unit of time.

Here you are asked to compare the speed of four objects moving in a circle. The four objects move in mostly different circles in different amounts of time. The equation for determining the speed of such objects is described in the Formula Frenzy section. As seen in the formula, the speed is dependent upon the R/T ratio. As the R/T ratio increases, the speed increases. So the ranking of the four objects in increasing order of speed will follow the same ranking of the ratio of R/T. It's time to use your calculator!

For objects that move in a circle, the speed (v) is the ratio of the circumference of the circle to the period (T) or time for one revolution.
R in the above equation represents the radius of the circle.