A block of mass M=8 kg is connected to an empty bucket of mass 1 kg by a massless cord running over an ideal pulley . The coefficients of static and kientic friction between table top and block are 0.5 and 0.4 respectively. Sand is gradually added to the bucket until the block just being to slide. The mass of sand added is: (g=10 m / s 2)

Question

A block of mass M=8 kg is connected to an empty bucket of mass 1 kg by a massless cord running over an ideal pulley . The coefficients of static and kientic friction between table top and block are 0.5 and 0.4 respectively. Sand is gradually added to the bucket until the block just being to slide. The mass of sand added is: (g=10 m / s 2) (A) 5 kg (B) 6 kg (C) 7 kg (D) 10 kg

Tardigrade Admin · Accepted Answer

For 8 kg block, <img class="img-fluid question-image" alt="image" src="https://cdn.tardigrade.in/img/question/physics/07cbf714f6b5b8702f0ffac044f1d0b8-.png" /> T = f L =0.5 × 8 g and for bucket, 2 T = mg ∴ m =8 kg mass of sand added =7 kg

5 kg

6 kg

7 kg

10 kg

For 8kg block, T=fL​=0.5×8g and for bucket, 2T=mg ∴m=8kg mass of sand added =7kg

For $8 k g$ block,

$T = f_{L} = 0.5 \times 8 g$
and for bucket, $2 T = m g$
$∴ m = 8 k g$
mass of sand added $= 7 k g$