How Does a Speck of Dust Affect the Motion of a Box on an Inclined Ramp?

[joemost12]

Yes, this gives you another equation to work with. You should be careful with the signs. When the block accelerates up the incline, the pulley will rotate clockwise. So, it is a good idea to take clockwise rotation as the positive direction for torque and angular acceleration.



Think about whether or not the right hand side should be zero.

Nope.. it shouldn't be.. it should be equal to Ma A, not 0

 

[TSny]

Yes. It will be important to distinguish between the acceleration of block A and the acceleration of block B. So, I suggest writing the right side as M_Aa_A. You can use the toolbar to enter superscripts and subscripts.

 

[joemost12]

Oh, I assumed the two blocks would have the same acceleration as they are all in the same system...

Shouldn't acceleration of A be equal to acceleration of B?

 

[TSny]

Oh, I assumed the two blocks would have the same acceleration as they are all in the same system...

Shouldn't acceleration of A be equal to acceleration of B?

The two accelerations would be equal if the string on the left side of the pulley (connected to block A) were parallel to the incline. You will need to determine the relationship between a_A and a_B.