What Torque is Needed to Accelerate a Phonograph Album?

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To calculate the torque needed to accelerate a phonograph album weighing 75 grams with a diameter of 30 cm at an angular acceleration of 3 rad/s², the formula T = Iα is used. The moment of inertia for a disc is given by I = 1/2 MR². Participants express frustration over the lack of understanding and resources, with one user acknowledging the difficulty of applying theoretical equations to practical problems. The discussion highlights the balance between providing assistance and encouraging independent learning. Ultimately, the conversation emphasizes the importance of grasping fundamental physics concepts for problem-solving.
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1.How much torque is required to accelerate a phonograph album (75-g, 30-cm diameter 33.3 rpm) at 3-rad/sec2


2. T=I(alpha)



3. Sorry i have to idea on this one I am completely lost!
 
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\tau = I\alpha as you stated.
You are given \alpha = 3 \theta s^{-1}
So just multiply by moment of inertia.

Hint: For a disc it's I = \frac{1}{2}MR^2
 
Rake, you are not helping here. The OP should know some of this stuff, or should at least know how to look it up. When you give out too much information you are helping students get their homework finished (you are doing it for them, for free), but you are not helping them learn.
 
Well the fact that I don't own a physics book and My teacher only gives us equations with variables for numbers and variables for more numbers and only gives examples of when used in real life. i would say that at least that is teaching me something thanks rake it helped me get that problem done on to the next one that was easy b/c of your help
 
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