Question

A farmer has to go $500m$ due north, $400m$ due east and $200m$ due south to reach his field. If he takes $20$ minutes to reach the field. What is the average velocity of farmer during the walk?

• A. $25m/min$
  
• B. $50m/min$
  
• C. $55m/min$
  
• D. $110m/min$
  

Answer 1

The correct option is A $25m/min$

Displacement of the farmer $\overrightarrow{S}=500\hat{j}+400\hat{i}-200\hat{j}=400\hat{i}+300\hat{j}$

Magnitude of the displacement $|\overrightarrow{S}|=\sqrt{{400}^2+{300}^2}=500$ m

Total time taken $t=20$ min

$\therefore$ Average velocity of the farmer $=\frac{|\overrightarrow{S}|}{t}=\frac{500}{20}=25$ m/min