A hockey puck having a mass of 0.3 kg is slid across the ice, starting with a speed of 2 m/s and slowing to 1 m/s after traveling for 3 s. What is the coefficient of friction between the puck and the ice

Respuesta :

Answer:

[tex]\mu_{k} = 0.034[/tex]

Explanation:

Let assume that hockey puck is moving on a horizontal ground. The corresponding equations of equilibrium for the hockey puck are:

[tex]\Sigma F_{x} = -\mu_{k}\cdot N = m\cdot a\\\Sigma F_{y} = N - m\cdot g = 0[/tex]

The following expression is built after some algebraic handling:

[tex]-\mu_{k}\cdot m\cdot g = m\cdot a[/tex]

The deceleration experimented by the object is:

[tex]a = \frac{1\,\frac{m}{s}-2\,\frac{m}{s}}{3\,s}[/tex]

[tex]a = -0.333\,\frac{m}{s^{2}}[/tex]

The kinetic coefficient of friction is:

[tex]\mu_{k} = -\frac{a}{g}[/tex]

[tex]\mu_{k} = - \frac{(-0.333\,\frac{m}{s^{2}}) }{9.807\,\frac{m}{s^{2}} }[/tex]

[tex]\mu_{k} = 0.034[/tex]