Question

An ant drags a piece of sweet on a straight path from the origin of the co-ordinate axes (0,0), to the point (3,4) (1 unit = 1 metre). What is the work done by the ant, if she applies a force of $1N$ ?

• A. $1J$
• B. $3J$
• C. $5J$
• D. $7J$

Answer 1

The correct option is C $5J$

Given: Force applied, $F=1N$, initial point = (0,0) (origin), final point = (3,4).
Let the displacement of the sweet be $s$ and the work done be $W$.

As the ant follows a straight path from the origin:
Displacement = distance from origin to point (3,4).
$\Rightarrow s=\sqrt{x^2+y^2}=\sqrt{3^2+4^2}=\sqrt{9+16}\therefore s=5m$

Work done $=\text{Force}\times \text{displacement}$
$\Rightarrow W=F\times s=1\times 5=5J$

Therefore, work done by the ant is $5J$