Find Angular Acceleration: Torque & Rotational I

In summary, the conversation discusses a figure with two objects attached to the end of a rigid rod on a frictionless surface. A vertical rod with a mass of m at the top and 2m at the bottom is acted upon by a horizontal and rightward force, resulting in a rotational acceleration of kF/(mL) about its center of mass. The center of mass is found to be 2/3 L below mass m, and the concept of torque is brought up in relation to the figure. The question of what K represents is also raised.
  • #1
wushumaster
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Homework Statement


The figure shows a view from above of two objects attached to the end of a rigid massless rod at rest on a frictionless table. Imagine a vertical rod, on the top end is a mass of m, an the bottom is a mass of 2m. The length of the rod is L and L/4 down from m (at top), a horizontal and rightward force is applied. When this F is applied, the resulting rotational acceleration of the rod about its center of mass is kF/(mL).

Homework Equations


What is K?

The Attempt at a Solution


So I found the center of mass as 2/3 L below mass m. but I don't understand how we can get torque (like I know its r cross F), but.. We can use torque=I times angular acceleration. But i got I wrong. HELP! please!
 
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  • #2
oh! is it just because torque equals r cross f and that means it equals 2/3 L- 1/4 L?
 

1. What is angular acceleration?

Angular acceleration is the rate of change of angular velocity in a rotating body. It is measured in radians per second squared (rad/s^2).

2. How is angular acceleration related to torque?

Angular acceleration is directly proportional to torque and inversely proportional to the moment of inertia of the rotating body. This can be represented by the equation α = τ/I, where α is angular acceleration, τ is torque, and I is moment of inertia.

3. What is the difference between linear and angular acceleration?

Linear acceleration refers to the change in linear velocity of an object, while angular acceleration refers to the change in angular velocity of a rotating object. Linear acceleration is measured in meters per second squared (m/s^2), while angular acceleration is measured in radians per second squared (rad/s^2).

4. How can I calculate angular acceleration?

Angular acceleration can be calculated by dividing the change in angular velocity by the time interval in which the change occurs. This can be represented by the equation α = (ω2 - ω1)/Δt, where α is angular acceleration, ω2 and ω1 are the final and initial angular velocities, and Δt is the time interval.

5. What factors affect angular acceleration?

The main factors that affect angular acceleration are torque and moment of inertia. A higher torque or a lower moment of inertia will result in a higher angular acceleration. Other factors that can affect angular acceleration include the shape and mass distribution of the rotating body, as well as any external forces acting on it.

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