Question

A FORCE OF 10N ACTS ON A BODY OF MASS 1KG AT REST. THE WORKDONEBYTHE BODY IN 4 SECONDS IS​

Answer 1

$\huge{\underline{\underline{\red{\mathfrak{AnSwEr :}}}}}$

Given :

• Force = 10 N
• Mass of body = 1 kg
• Time = 4 s
• Initial velocity (u) = 0 m/s

__________________

To Find :

• Work Done

__________________

Solution :

Use formula for Force :

$\large{\boxed{\sf{F \: = \: ma}}} \\ \\ \implies {\sf{a \: = \: \dfrac{F}{m}}} \\ \\ \implies {\sf{a \: = \: \dfrac{10}{1}}} \\ \\ \implies {\sf{a \: = \: 10}} \\ \\ {\underline{\sf{\therefore \: Acceleration \: is \: 10 \: ms^{-2}}}}$

_________________________

Now use formula for displacement

$\large {\boxed{\sf{s \: = \: ut \: + \: \dfrac{1}{2}at^2}}} \\ \\ \implies {\sf{s \: = \: 0 \: \times \: 4 \: + \: \dfrac{1}{2} \: \times \: 10 \: \times \: (4)^2}} \\ \\ \implies {\sf{s \: = \: \dfrac{1}{2} \: \times \: 10 \: \times \: 16}} \\ \\ \implies {\sf{s \: = \: 10 \: \times \: 8}} \\ \\ \implies {\sf{s \: = \: 80}} \\ \\ {\underline{\sf{\therefore \: Displacement \: is \: 80 \: m}}}$

__________________________

Now use Formula for Work Done

$\large{\boxed{\sf{W \: = \: F.s}}} \\ \\ \implies {\sf{W \: = \: 10 \: \times \: 80}} \\ \\ \implies {\sf{W \: = \: 800}} \\ \\ {\underline{\sf{\therefore \: Work \: Done \: is \: 800 \: J}}}$

Answer 2

$\large \bigstar\boxed{\bf \red{ GIVEN}} \bigstar \\ \\ \Longrightarrow \bf F= 10 \: N \\ \\\Longrightarrow \bf mass = 1 \: kg \\ \\\Longrightarrow \bf Time = 4 \: sec \\ \\ \Longrightarrow \bf u = 0 \: m {s}^{ - 1}$

$\large \bigstar\boxed{\bf \red{ TO \: FIND}} \bigstar \\ \\\Longrightarrow \bf Work \: done \: by \: the \: body$

$\large \bigstar\boxed{\bf \red{ SOLUTION}} \bigstar \\ \\ \large \boxed{ \bf \blue{F = ma}} \\ \\ \Longrightarrow \bf a = \frac{F}{m} \\ \\ \Longrightarrow \bf a = \frac{10}{1} \\ \\ \boxed{ \bf a = 10 \: m {s}^{ - 2}}$

$\large \boxed{\bf \green{s = ut + \frac{1}{2} a {t}^{2} }} \\ \\ \Longrightarrow \bf s = 0 \times 4 + \frac{1}{2} \times 10 \times {4}^{2} \\ \\\Longrightarrow \bf s = \frac{1}{2} \times 10 \times 16 \\ \\\Longrightarrow \bf s = \frac{160}{2} \\ \\ \boxed{ \bf s = 80 \: m}$

$\boxed{ \bf \pink {Work = Dorce \times Displacement }}\\ \\ \bf Work = 10 \times 80 \\ \\ \large \boxed{ \bf \orange{ Work = 800 \:J}}$