Question

An object of mass 5kg is moving with a velocity of 10m/s. A force is applied so that in 10 sec, it attains a velocity of 30m/s. What is the force applied on the object

Answer 1

Answer:

Given:

Initial velocity = 10 m/s

Final velocity = 30 m/s

Time taken = 10 seconds.

Mass of car = 5 kg

To find:

Force applied on the object

Concept:

Whenever the velocity of the object changes with respect to time , the object experiences acceleration. And the acceleration multiplied with the mass of object shall give us the Force.

Calculation:

Applying Equations of Motions :

$\bigstar \: \: v = u + at$

$= > a = \dfrac{v - u}{t}$

$= > a = \dfrac{30 - 10}{10}$

$= > a = 2 \: m {s}^{ - 2}$

Force applied be F ;

$\bigstar \: \: F = m \times a$

$= > F = 5 \times 2$

$= > F = 10 \: N$

So final answer :

Force applied = 10 N

Answer 2

Answer:

$\frak{Given}\begin{cases}\textsf{Mass of Car (m) = 5 kg}\\\textsf{Initial Velocity (u) = 10 m/s}\\\textsf{Final Velocity (v) = 30 m/s}\\\textsf{Time (t) = 10 sec}\end{cases}$

$\underline{\bigstar\:\textbf{By First Equation of Motion :}}$

$:\implies\sf v = u+at\\\\\\:\implies\sf 30=10+(a \times 10)\\\\\\:\implies\sf 30-10=10a\\\\\\:\implies\sf 20=10a\\\\\\:\implies\sf \dfrac{20}{10}=a\\\\\\:\implies\sf a=2\:m/s$

$\rule{150}{1}$

$\boxed{\bf{\mid{\overline{\underline{\bigstar\:Force\: Applied :}}}}\mid}$

$\dashrightarrow\sf\:\:Force=Mass \times Acceleration\\\\\\\dashrightarrow\sf\:\:Force=5\:kg \times 2\:m/s\\\\\\\dashrightarrow\:\:\underline{\boxed{\sf Force=10\:N}}$

⠀

$\therefore\:\underline{\textsf{Force applied on object is \textbf{10 Newton}}}.$