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A point moves along a circle with a spee...

A point moves along a circle with a speed `v=kt` , where `K=0.5m//s^(2)`
Find the total acceleration of the point the momenet when it has covered the `n^(th)` Fraction of the circle after the beginging of motion, where `n=(1)/(10)` .

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To solve the problem, we need to find the total acceleration of a point moving along a circular path with a speed that varies with time as \( v = kt \), where \( k = 0.5 \, \text{m/s}^2 \). We are to find the total acceleration when the point has covered the \( n^{th} \) fraction of the circle, where \( n = \frac{1}{10} \). ### Step-by-Step Solution: 1. **Understanding the Speed Function**: The speed of the point is given by: \[ v = kt \] where \( k = 0.5 \, \text{m/s}^2 \). 2. **Finding the Displacement**: The displacement \( s \) can be found by integrating the speed: \[ s = \int v \, dt = \int kt \, dt = \frac{1}{2} kt^2 \] Therefore, the displacement after time \( t \) is: \[ s = \frac{1}{2} k t^2 \] 3. **Relating Displacement to Circle**: Since the point covers a fraction \( n \) of the circle, we can express the displacement in terms of the radius \( r \) of the circle: \[ s = 2 \pi r n \] Setting the two expressions for \( s \) equal gives: \[ \frac{1}{2} kt^2 = 2 \pi r n \] 4. **Solving for Time \( t \)**: Rearranging the equation to find \( t^2 \): \[ t^2 = \frac{4 \pi r n}{k} \] 5. **Finding Tangential Acceleration \( a_t \)**: The tangential acceleration is the derivative of speed with respect to time: \[ a_t = \frac{dv}{dt} = k \] Since \( k = 0.5 \, \text{m/s}^2 \), we have: \[ a_t = 0.5 \, \text{m/s}^2 \] 6. **Finding Normal Acceleration \( a_n \)**: The normal (centripetal) acceleration is given by: \[ a_n = \frac{v^2}{r} \] Substituting \( v = kt \) gives: \[ a_n = \frac{(kt)^2}{r} = \frac{k^2 t^2}{r} \] Now substituting \( t^2 \) from step 4: \[ a_n = \frac{k^2 \left(\frac{4 \pi r n}{k}\right)}{r} = \frac{4 \pi k n}{1} \] 7. **Calculating Total Acceleration**: The total acceleration \( a \) is the vector sum of tangential and normal accelerations: \[ a = \sqrt{a_t^2 + a_n^2} \] Substituting the values: \[ a = \sqrt{(0.5)^2 + (4 \pi k n)^2} \] 8. **Substituting Values**: With \( k = 0.5 \) and \( n = 0.1 \): \[ a_n = 4 \pi (0.5)(0.1) = 0.2 \pi \] Now substituting back into the total acceleration: \[ a = \sqrt{(0.5)^2 + (0.2 \pi)^2} \] 9. **Calculating the Final Result**: \[ a = \sqrt{0.25 + (0.2 \cdot 3.14)^2} = \sqrt{0.25 + 0.0396} = \sqrt{0.2896} \approx 0.54 \, \text{m/s}^2 \] ### Final Answer: The total acceleration of the point when it has covered the \( \frac{1}{10} \) fraction of the circle is approximately \( 0.54 \, \text{m/s}^2 \).

To solve the problem, we need to find the total acceleration of a point moving along a circular path with a speed that varies with time as \( v = kt \), where \( k = 0.5 \, \text{m/s}^2 \). We are to find the total acceleration when the point has covered the \( n^{th} \) fraction of the circle, where \( n = \frac{1}{10} \). ### Step-by-Step Solution: 1. **Understanding the Speed Function**: The speed of the point is given by: \[ v = kt ...
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