Question

The relationship between force and position is shown in the figure given (in one-dimensional case). Calculate the work done by the force in displacing a body from $x=0\text{cm}$ to $x=5\text{cm}$.

• A. $30ergs$
  
• B. $70ergs$
  
• C. $20ergs$
  
• D. $60ergs$
  

Answer 1

The correct option is A $30ergs$

Numerical addition of area under the curve of force and displacement gives work done.

So for displacement upto 2cm

Area$=10\times 2=20$

For displacememt 2 to 3cm

Area$=20\times 1=20$

For displacement 3 to 4cm

Area$=-20\times 1=20$

For displacement 4 to 5cm

Area$=10\times 1=10$

Adding numerically we get work done is $30erg$

Cgs Unit of work done is erg.