A cart of mass 0.68 kg is attached to one end of of a spring and placed on a low-friction track, inclined at an angle of 61.5 degrees with respect to the horizontal. The cart is found to be in equilibrium when the spring is stretched to a total length of 52.0 cm. Given that the rest length for the spring is 12 cm, what is the spring constant for the spring

Respuesta :

Answer:

The value is [tex]k = 29.28 \ N / m[/tex]

Explanation:

From the question we are told that

The mass of the cart is  m  =  0.68 kg

The angle of inclination is [tex]\theta = 61.5^o[/tex]

The length of the spring when the cart is a equilibrium is  [tex]d = 52.0 \ cm = 0.52 \ m[/tex]

The length of the spring when at rest is  [tex]d_r = 12 \ cm = 0.12 \ m[/tex]

Generally the weight of the cart is mathematically represented as

      [tex]W_c = m * g * sin (\theta )[/tex]

=>    [tex]W_c = 0.68 * 9.8 * sin (61.5 )[/tex]

=>    [tex]W_c = 5.856 \ N[/tex]

Generally the force applied on the spring by the weight of the cart is mathematically represented as

       [tex]F = \frac{1}{2} * k * (d - d_r )[/tex]

So at equilibrium

        [tex]W_c = F[/tex]

=>   [tex]\frac{1}{2} * k * (d - d_r ) = 5.856[/tex]

=>   [tex]0.5 * k * (0.52 - 0.12 ) = 5.856[/tex]

=>   [tex]k = 29.28 \ N / m[/tex]