Question

a block of mass 1.5 kg placed on a rough horizontal surface is pulled by a constant horizontal force of 1.2 kg-f. The coefficient of friction between the block and and the surface is 0.3. Find the acceleration produced in terms of g.

Answer 1

this may help u........

Answer 2

first of all, we have to check block of mass 1.5kg moves or not.
find static friction , $f_s$
we know, $f_s=\mu_s N$
= 0.3 × mg = 0.3 × 1.5 × 10 = 4.5 N

but force is applied 1.2kg-f or 12N
here we can see that applied force is greater than static friction so, block moves with an acceleration .
Let acceleration of block is a.

$F-f_s=ma$

12 - 4.5 = 1.5 × a

7.5 = 1.5 × a => a = 5 m/s²