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could some on help me understand why the following is true?

for some of them i wrote exactly what i don't understand, for others

i really have no idea

Two uniform rods are connected to a table by pivots at one end. Rod B is longer than rod A. Both are released simultaneously from an initial angle θ. Neglect air friction. NOTATION: CM = center of mass; α = angular acceleration; |ay|= size of downward acceleration.

True: αA and αB are dependent on θ.

just don't understand why.

False: |ax| of the CM initially equals 0 for both rods.

this would be false because of the centr. force right?

True: |ay| is initially equal for the CM of A and B.

that is because it is g right?

True: Just before landing, the CM of B has a greater speed than the CM of A.

why so? i found an explanation on the internet but there they comapered mgh to 0.5Iw^2

and from there proved b's speed is larger therfore the answer.

but why can i use such an equation? why do i not take into consideration the kinetic energy

of center of mass and how do i define the height here? according to the center of mass?

False: Rods A and B hit the table at the same time.

False: αA and αB are the same initially.

True: αA and αB both increase with time.

thanks

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# Homework Help: Torque and accleration

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