A circular disc `X` of radius `R` is made from an iron plate of thickness `t`, and another plate `Y` of radius `4R` is made from an iron plate of thickness `t//4`. The ratio between moment of inertia `I_(Y)//I_(X)` isA. `32`B. `16`C. `1`D. `64`

A circular disc `X` of radius `R` is made from an iron plate of thickn

1.	A circular disc `X` of radius `R` is made from an iron plate of thickness `t`, and another plate `Y` of radius `4R` is made from an iron plate of thickness `t//4`. The ratio between moment of inertia `I_(Y)//I_(X)` isA. `32`B. `16`C. `1`D. `64`
Answer» Correct Answer - D `I_(X) = (1)/(2) ("mass") ("radius")^(2)` `= (1)/(2) [(piR^(2))t.rho] R^(2)` ltbr. `I_(Y) = (1)/(2) [(pi 10 R^(2)) (t.rho)/(4)](4R)^(2) = 64 I_(X)`

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A circular disc `X` of radius `R` is made from an iron plate of thickness `t`, and another plate `Y` of radius `4R` is made from an iron plate of thickness `t//4`. The ratio between moment of inertia `I_(Y)//I_(X)` isA. `32`B. `16`C. `1`D. `64`

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