Question

A body of mass $1\text{kg}$ is subjected to a force of $20\text{N}$ for $10$ seconds after which the force ceases to act. What distance would it travel in the next $10$ seconds?

• A. $2\text{km}$
• B. $3\text{km}$
• C. $4\text{km}$
• D. $5\text{km}$

Answer 1

The correct option is A $2\text{km}$

For $AB:$
Acceleration can be given as $a=\frac{\text{Force}}{\text{Mass}}=\frac{20\text{N}}{1\text{kg}}=20{\text{m/s}}^2$
Velocity of the body after first $10\text{s}=v_B=u+at=20\times 10=200\text{m/s}$
For $BC:$
As there is no force acting on the body in this part so,
Acceleration $=0$
$\therefore$ Distance travelled by the body in next $10\text{s}=BC=v_B\times t=200\times 10$
$=2000\text{m}=2\text{km}$