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A body of mass m = 10 kg is attached to ...

A body of mass m = 10 kg is attached to a wire of length 0.3m. The maximum angular velocity with which it can be rotated in a horizontal circle is (Given, breaking stress of wire `= 4.8 xx 10^(7) Nm^(-2)` and area of cross-section of a wire `= 10^(-6) m^(2)`)

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To find the maximum angular velocity with which a body can be rotated in a horizontal circle while attached to a wire, we will follow these steps: ### Step 1: Calculate the maximum tension in the wire using breaking stress. The breaking stress (σ) is given by the formula: \[ \sigma = \frac{F}{A} \] Where: - \( F \) is the force (tension in the wire), - \( A \) is the area of cross-section of the wire. Given: - Breaking stress \( \sigma = 4.8 \times 10^7 \, \text{N/m}^2 \) - Area of cross-section \( A = 10^{-6} \, \text{m}^2 \) Rearranging the formula to find \( F \): \[ F = \sigma \times A \] Substituting the values: \[ F = (4.8 \times 10^7) \times (10^{-6}) = 48 \, \text{N} \] ### Step 2: Relate the tension in the wire to the centripetal force. When the body is rotating in a horizontal circle, the tension in the wire provides the centripetal force required for circular motion. The centripetal force \( F_c \) is given by: \[ F_c = m \omega^2 r \] Where: - \( m \) is the mass of the body, - \( \omega \) is the angular velocity, - \( r \) is the radius of the circular path (which is equal to the length of the wire). Given: - Mass \( m = 10 \, \text{kg} \) - Length of the wire (which is the radius \( r \)) = 0.3 m ### Step 3: Set the tension equal to the centripetal force. We know that the maximum tension \( F \) is equal to the centripetal force: \[ F = m \omega^2 r \] Substituting the values we have: \[ 48 = 10 \omega^2 (0.3) \] ### Step 4: Solve for \( \omega^2 \). Rearranging the equation to solve for \( \omega^2 \): \[ 48 = 3 \omega^2 \quad (\text{since } 10 \times 0.3 = 3) \] \[ \omega^2 = \frac{48}{3} = 16 \] ### Step 5: Calculate \( \omega \). Taking the square root to find \( \omega \): \[ \omega = \sqrt{16} = 4 \, \text{rad/s} \] ### Final Answer: The maximum angular velocity with which the body can be rotated in a horizontal circle is \( \omega = 4 \, \text{rad/s} \). ---
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