Question

a body of mass 4kg moving with uniform velocity of 5m/s .it is reacted upon a force of 12 newton.what will be it's velocity after 1second

Answer 1

F = ma
F = m(v - u) / t
12 N = 4 kg × (v - 5 m/s) / 1 s
v = 8 m/s

It’s velocity after 1 second is 8 m/s

Answer 2

$\huge\purple{ \underline{ \boxed{\mathbb{\red{QUESTION : }}}}}$

A body of mass 4 kg is moving with uniform velocity of 5m/s . It is reacted upon by a force of 12 N .What will be it's velocity after 1 second ?

$\huge\purple{ \underline{ \boxed{\mathbb{\red{ANSWER : }}}}}$

Final velocity of body = 8 m/s

$\huge\purple{ \underline{ \boxed{\mathbb{\red{EXPLANATION : }}}}}$

$\green{ \large \underline{ \mathbb{\underline{GIVEN : }}}}$

Mass of body ( m ) = 4 kg

Force ( F ) = 12 N

Time taken ( t ) = 1 s

Initial velocity ( u ) = 5 m/s

$\green{ \large \underline{ \mathbb{\underline{TO \: FIND : }}}}$

Final velocity of body .

$\green{ \large \underline{ \mathbb{\underline{FORMULAS \: USED : }}}}$

$\purple{ \boxed{ \bf a = \frac{v - u}{t} }}$

$\purple{ \boxed{ \bf F = ma}}$

$\green{ \large \underline{ \mathbb{\underline{SOLUTION: }}}}$

$\displaystyle \sf \longrightarrow F = ma \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow F = m \bigg( \frac{v - u}{t} \bigg) \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow F = \frac{m(v - u)}{t} \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow F = \frac{mv - mu}{t} \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow 12 = \frac{4(v) - 4(5)}{1} \: \\ \\ \displaystyle \sf \longrightarrow 12 = 4v - 20 \: \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow 4v - 20 = 12 \: \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow 4v = 12+ 20 \: \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow 4v = 32 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \displaystyle \sf \longrightarrow v = \frac{32}{4} \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ \ \displaystyle \sf \longrightarrow v = 8 \: m {s}^{ - 1} \: \: \: \: \: \: \: \: \: \:$

$\purple{\boxed{\begin{array}{l} \sf{Final \: velocity \: of \: body = 8 \: m {s}^{ - 1}} \end{array}}}$

$\green{ \large \underline{ \mathbb{\underline{KNOW\:MORE: }}}}$

• Acceleration

Acceleration is the rate at which velocity changes with time .

• Initial Velocity

Initial velocity is the velocity of the object before the effect of acceleration .

• Final Velocity

Final velocity is the velocity of the object after the effect of acceleration .

• Force

Force is the push or pull on an object with mass that causes it to change its velocity.

$\Large{\purple{\boxed{\begin{array}{l} \textsf{Equations of motion : } \\ \\ \textsf{v = u + at} \\ \\ \displaystyle\textsf{s = ut + \sf\frac{1}{2}a {t}^{2} } \\ \\ \sf {v}^{2} - {u}^{2} = 2as \end{array}}}}$