contestada

An electric clock is hanging on the wall in the living room. The clock is unplugged, and the second hand comes to a halt over a brief period of time. During this period, what is the direction of the angular acceleration of the second hand?

Respuesta :

Answer:

Explanation:

angular velocity of second is given by

[tex]\omega_0=\frac{2\pi }{60}=\frac{\pi }{30}\ rad/s[/tex]

suppose clockwise motion is positive

It is given that second hand halt over a brief period of  time

using

[tex]\omega =\omega _0+\alpha \cdot t[/tex]

[tex]\omega =final\ angular\ velocity[/tex]

[tex]\omega _0=initial\ angular\ velocity[/tex]

[tex]\alpha =angular\ acceleration[/tex]

[tex]t=time[/tex]

[tex]\alpha =-\frac{\omega _0}{t}[/tex]

[tex]\alpha =-\frac{\pi }{30t}\ rad/s^2[/tex]

so direction of angular acceleration is anti-clockwise(opposite to angular velocity) as it try to cease the motion