A uniform disc of mass `M` and radius `R` is liffted using a string as shown in the figure. Then choose incorrect option(s),

Options

A. its linear acceleration is g upward
B. its linear acceleration is g downward
C. its angular acceleration is `(2g)/(R )` .
D. its rate of change of angular momentum is `MgR` .

Answer

B

Explanation

A uniform disc ……………..
`(3Mg)/(2)+(Mg)/(2)-Mg=Ma`
`a = g uarr`
`tau = I alpha`
`(3Mg)/(2)R -(Mg)/(2)R = (MR^(2))/(2).alpha`
`2Mg alpha = (2g)/(R )`