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question 11
5 points
a ball moves with a constant speed of 4 m/s around a circle of radius 0.25 m. what is the period of the motion?
0.4 s
2 s
0.7 s
1 s
0.1 s

Explanation:

Step1: Find the circumference of the circle

The formula for the circumference of a circle is $C = 2\pi r$. Given $r = 0.25$ m, so $C=2\pi\times0.25=\frac{\pi}{2}$ m.

Step2: Use the speed - distance - time relationship

The speed formula is $v=\frac{d}{t}$. Here, $d = C$ (distance traveled in one period) and $v = 4$ m/s. We want to find the period $T$ (time for one full - circle motion), so $T=\frac{C}{v}$. Substituting $C=\frac{\pi}{2}$ m and $v = 4$ m/s, we get $T=\frac{\frac{\pi}{2}}{4}=\frac{\pi}{8}\approx0.4$ s.

Answer:

0.4 s