A turntable is off and is not spinning. A 0.8 g ant is on the disc and is 9 cm away from the center. The turntable is turned on and 0.8 s later it has an angular speed of 45 rpm. Assume the angular acceleration is constant and determine the following quantities for the ant 0.4 s after the turntable has been turned on. Express all quantities using appropriate mks units.

Respuesta :

Complete Question

The complete is shown on the first uploaded image

Answer:

[tex]\alpha = 5.89 rad/s^2[/tex]

[tex]w__{0.4}}= 2.36 \ rad/s[/tex]

[tex]v= 0.212m/s[/tex]

[tex]a_t= 0.5301 m/s[/tex]

[tex]a_r = 0.499 m/s[/tex]

[tex]a = 0.7279 m/s[/tex]

[tex]F_{net}=5.823*10^{-4}N[/tex]

Explanation:

From the question we are told that

       mass of the ant is [tex]m_a = 0.8g = \frac{0.8}{1000} = 0.00018kg[/tex]

         The distance from the center is [tex]d = 9cm = \frac{9}{100} = 0.09m[/tex]

         The angular speed is [tex]w = 45rpm = 45 * \frac{2 \pi }{60} = 1.5 \pi[/tex]

          The time taken to attain  angular acceleration of 45rpm [tex]t_1 = 0.8s[/tex]

           The time taken is [tex]t_2 = 0.4 s[/tex]

The  angular acceleration is mathematically represented as

                       [tex]\alpha = \frac{w}{t}[/tex]  

                          [tex]= \frac{1.5}{0.8}[/tex]

                           [tex]\alpha = 5.89 rad/s^2[/tex]

   The angular velocity at time t= 0.4s is mathematically represented as

                         [tex]w__{0.4s}} = \alpha * t_2[/tex]          Recall angular acceleration is constant

                                 [tex]= 5.89 * 0.4[/tex]

                                 [tex]w__{0.4}}= 2.36 \ rad/s[/tex]

The linear velocity is mathematically represented as

                 [tex]v = w__{t_2}} * r[/tex]

                    [tex]= 2.36 * 0.09[/tex]

                    [tex]v= 0.212m/s[/tex]

The tangential acceleration is mathematically represented as

                [tex]a_{t} = \alpha * r[/tex]

                      [tex]= 5.89 * 0.09[/tex]

                      [tex]a_t= 0.5301 m/s[/tex]

The radial acceleration is mathematically represented as

                  [tex]a_r = \frac{v^2}{r}[/tex]

                       [tex]= \frac{0.212^2}{0.09}[/tex]

                  [tex]a_r = 0.499 m/s[/tex]

The resultant velocity is mathematically represented as

                 [tex]a = \sqrt{a_t^2 + a_r^2}[/tex]

                     [tex]= \sqrt{0.53^2 + 0.499^2}[/tex]

                  [tex]a = 0.7279 m/s[/tex]

The net force is mathematically represented as

        [tex]F_{net} = 0.0008 * 0.7279[/tex]

                 [tex]F_{net}=5.823*10^{-4}N[/tex]

     

             

                                                     

Ver imagen okpalawalter8