In the apparatus shown above, one end of a string of length L is attached to a block of mass M and the other end is connected to the axle of a motor that rotates, causing the block to move in a circle of radius R at a constant speed vT such that the string makes an angle θ with the vertical. A student wants to use the apparatus to make measurements and create a graph that can be used to estimate the acceleration g due to gravity at the surface of Earth. The student can adjust the motor to achieve different tangential speeds of the block

Respuesta :

Newton's second law allows finding the result for the type of graph to find the gravity acceleration  is:

  • The student must make a graph of the tangential velocity versus the tangent of the angle and of the slope to find the value of gravity.

                     g = [tex]\frac{slope}{\sqrt{L} }[/tex]

Oscillatory motion is a simple harmonic motion where the restoring force is proportional to the displacement.

Newton's second law gives a relationship between the net force, the mass and the acceleration of a body, in the attached we can see a free body diagram of the system, let's apply Newton's second law.

                 [tex]t_y - W =0 \\T_x = m a[/tex]

Since the movement is circular, the acceleration is centripetal.

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

Let's substitute.

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

Let's use trigonometry to find the radius of the circle and the stress component.

              sin θ = [tex]\frac{r}{L}[/tex]  

              r = L sin  θ

             sin θ =  [tex]\frac{T_x}{T}[/tex]  

             cos θ = [tex]\frac{T_y}{T}[/tex]  

             Tₓ = T sin θ

             [tex]T_y[/tex] = T cos θ

Let's substitute.

            T sin θ = [tex]\frac{m v^2 }{L sin \theta }[/tex]  

            T sin² θ = [tex]\frac{m}{L} \ v^2[/tex]  

From the other equation.

             [tex]T_y= W \\T cos \theta = m g[/tex]  

Let's write our system of equations.

            T sin² θ  = [tex]\frac{m}{L} \ v^2[/tex]  

            T cos θ = m g

We solve the system by squaring the second equation and dividing.

             tan² θ = [tex]\frac{1}{g^2 L } \ v^2[/tex]  

             L g² tan² θ = v²

             

             v = g [tex]\sqrt{L}[/tex]  tan θ

Consequently, if the student makes a graph of the velocity versus the tangent of the angle, he obtains a straight line and the slope is:

             slope = g [tex]\sqrt{L}[/tex]

From this expression you can calculate the acceleration of gravity.

              [tex]g= \frac{slope}{\sqrt{L} }[/tex]  

In conclusion using Newton's second law we can find the result for the type of graph to find the gravity acceleration  is:

  • The student must make a graph of the tangential velocity versus the tangent of the angle and of the slope to find the value of gravity.

                 [tex]g = \frac{slope}{\sqrt{L} }[/tex]  

Learn more here:  brainly.com/question/17315536

Ver imagen moya1316