Question

The pulley shown in fig has MOI 0.5kg m² and radius 10 cm. Assuming no friction any where, find the acceleration of 4 kg block

• A. 1.11ms^-2
• B. 0.75 ms^-2
• C. 0.5 ms^-2
• D. 0.25 ms^-2

Answer 1

Answer: (D)

0.25 ms^-2

Answer 2

4 g cos 45 – T₁ = 4a ……….. (i)

(T₁ – T₂)R = Iα

or T₁ – T₂ = $\frac { \mathrm { I } } { \mathrm { R } ^ { 2 } } \mathrm { a }$ ………. (ii)

T₂ – 2g cos 45 = 2a ……. (iii)

Adding (i), (ii) and (iii) 2g cos 45 = 6a + $\frac { \mathrm { I } } { \mathrm { R } ^ { 2 } } \mathrm { a }$ or

a = $\frac { \sqrt { 2 } \times 10 } { 6 + 50 } = 0.25 \mathrm {~ms} ^ { - 2 }$