Register to reply 
Angular Acceleration Problem.. Why am I not right? 
Share this thread: 
#1
Oct1209, 07:51 AM

P: 93

1. The problem statement, all variables and given/known data
The blades in a blender rotate at a rate of 7900 rpm. When the motor is turned off during operation, the blades slow to rest in 4.0 s. What is the angular acceleration as the blades slow down? Vi= 7900 rpm = 82.72860654 rad/sec (This may be my error) Vf= 0 t= 4 secs 2. Relevant equations [tex] v = v_0 + a t [/tex] 3. The attempt at a solution I've tried solving for a in the answer above but the answer is incorrect.. I did: 0 = 82.72860654 + a(4) and when solved got an answer of 20.68215164. I'm unsure of why this is NOT correct. Any help is greatly appreciated. I think the problem may be in my conversions to rad/sec or maybe I am forgetting to convert something. 


#3
Oct1209, 08:08 AM

P: 93

(7900*2pi)/60 If I do this then I get 827.2860654. Does that sound correct? 


#5
Oct1209, 08:12 AM

P: 93




#6
Oct1209, 08:27 AM

Mentor
P: 41,477




#7
Oct1209, 10:16 AM

P: 93




Register to reply 
Related Discussions  
Angular Acceleration Problem  Introductory Physics Homework  6  
Another Angular Acceleration Problem  Introductory Physics Homework  4  
Angular Acceleration problem...  Introductory Physics Homework  2  
Angular acceleration problem  Introductory Physics Homework  9 