Question 123: Laws of Motion

Question

A block of mass 40 kg slides over a surface, when a mass of 4 kg 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
.)

Accepted Answer

$${f_{{r_{\max }}}} = \mu N$$
$$ = 0.02 	imes 400$$
= 8 N
Let the acceleration is a as shown then.
$$40 - T = 4a$$
$$T - 8 = 40a$$
$$ \Rightarrow a = {{32} \over {44}} = {8 \over {11}}$$ m/s
2

Answer

1 ms
$$-$$2

Answer

1/5 ms
$$-$$2

Answer

4/5 ms
$$-$$2

Answer

8/11 ms
$$-$$2

Laws of Motion

A block of mass 40 kg slides over a surface, when a mass of 4 kg 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 .)

Choose the correct answer: