Angular and tangential acceleration

[Idividebyzero]

1. What is the tangential acceleration of a bug
on the rim of a 78 rpm record of diameter
9.79 in. if the record moves from rest to its
final angular speed in 7 s? The conversion
between inches and meters is 0.0254 m/in.
Answer in units of m/s2.



2. angular acceleration



3. converted 9.79 inches to 0.248666 meters using 0.0254 m/in. converted 78 rev/min to 8.168 rad/s using 2pi rad / 60 sec. alpha = delta omega / delta time. getting alpha as 8.168 rad/s / 7s = 1.1668 rad/s/s. multiply 1.1668 rad/s/s * 0.24866 m to get 0.2901 m/s^2. this is incorrect

 

[rock.freak667]

a = alpha*r

you are multiplying by the diameter 'd' which is twice the radius 'r'.

 

[PhanthomJay]

It looks OK, but you should round it off to 1 significant figure. Edit: But first heed rockfreak's advice

 

[Idividebyzero]

haha yeah i was multiplying by the diameter that's probably the issue

 

[Idividebyzero]

that confirms it, yall found my tiny mistakes once again...gracias amegos