- Trending Categories
Data Structure
Networking
RDBMS
Operating System
Java
MS Excel
iOS
HTML
CSS
Android
Python
C Programming
C++
C#
MongoDB
MySQL
Javascript
PHP
Physics
Chemistry
Biology
Mathematics
English
Economics
Psychology
Social Studies
Fashion Studies
Legal Studies
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Certain force acting on a 20 kg mass changes its velocity from $5\ ms^{-1}$ to $2\ ms^{-1}$. Calculate the work done by the force.
Given:
mass $m=20\ kg.$
Initial velocity $u=5\ ms^{-1}$
Final velocity $v=2\ ms^{-1}$
To do: To calculate the work done by the force.
Solution:
As known, work done to change the velocity $=$ change in kinetic energy
$=K_2-K_1$
$=\frac{1}{2}mv^2-\frac{1}{2}mu^2$
$=\frac{1}{2}m( v^2-u^2)$
$=\frac{1}{2}\times20(2^2-5^2)$
$=10( 4-25)$
$=-21\times10$
$=-210\ Joule$
Thus, the work done to change the velocity is $210\ Joule$.
Advertisements