circular motion (f=ma)

Question

A 0.5 kg stone tied to a string moves in a horizontal circle of radius 1.2 m at constant speed 6 m/s. Find tension in the string.

RankGuru · Accepted Answer

1. **Centripetal Requirement**: For horizontal circular motion, the tension ($T$) in the string provides the necessary centripetal force ($F_c$).
2. **Formula**: $F_c = \frac{mv^2}{r}$.
3. **Identify Parameters**:
   - Mass ($m$) $= 0.5$ kg
   - Velocity ($v$) $= 6$ m/s
   - Radius ($r$) $= 1.2$ m
4. **Calculation**:
   - $T = \frac{0.5 	imes 6^2}{1.2}$
   - $T = \frac{0.5 	imes 36}{1.2} = \frac{18}{1.2}$
   - $T = 15$ N.
5. **Final Result**: The tension in the string is **$15$ N**.

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circular motion (f=ma)

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