Question

when a force of 40N applied on a body , it moves with an acceleration of 5m/s find the mass of a body​

Answer 1

8kg

Explanation:

F=ma

m=F/a

m=40/5

=8kg

Answer 2

$\huge\mathcal\colorbox{pink}{{\color{b}{Your Answerr}}}$

$\green{\textbf{We have, for the body:}}$

$\pink{\texttt{Force = 40 N}}$

$\pink{\texttt{Acceleration = 5 ms2}}$

$\green{\textbf{From Second law of motion :}}$

$\pink{\texttt{Force = mass × acceleration}}$

$mass = \frac{force}{acceleration}$

$\implies \: mass = \frac{40}{5} = 8 kg$

$\green{\textbf{Now, we have, for the body:}}$

$\pink{\texttt{Mass = 80 kg}}$

$\pink{\texttt{Initial velocity,u = 5 ms-1}}$

$\pink{\texttt{final velocity, v = 25 ms-1}}$

$\pink{\texttt{Time, t = 2 sec}}$

$\green{\textbf{From the second law of the motion,}}$ we know that the rate of change of momentum is equal to force applied. Therefore,

$F = \frac{m(v - u)}{t} = \frac{80(25 - 5)}{2} = 800 \: N$

$\huge\mathcal\colorbox{pink}{{\color{b}{Hope this helps...}}}$