A block of mass 40kg slides over a surface, when a mass of 4kg is suspended through an inextensible massless string passing over frictionless pulley as shown below.

The coefficient of kinetic friction between the surface and block is 0.02. The acceleration of block is. (given g = 10 ms^-².)

Option 1 -

1 ms^-2

Option 2 -

1/5 ms^-2

Option 3 -

4/5 ms^-2

Option 4 -

8/11 ms^-²

4 Views | Posted 2 weeks ago

Asked by Shiksha User

1 Answer

Answered by

alok kumar singh | Contributor-Level 10

2 weeks ago

Correct Option - 4

Detailed Solution:

According to Newton’s laws of motion, we can write

4a = 4g – T . (1), and

40a = T - f_k = T $μ$ - (40g) ……………… (2)

Adding equations (1) and (2), we can write

44a = 40 – 0.02 × (400) = 32

$\Rightarrow a = \frac{32}{44} = \frac{8}{11} m / s^{2}$

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