Question

If the velocity of a car is 45 kilometers per hour west, how far can it travel in 0.5 hours?

Answer 1

Hint: In the above problem, we see that we have been given the velocity of car and the total distance has been asked. We know that velocity is a vector quantity and distance is a scalar quantity, so there is no need or use of the direction in which the car is moving and we can solve the problem without it.

Complete answer:
Now, this is a question of application of distance formula. The distance formula can be stated as, if an object is moving at a constant speed, then the total distance travelled by the object in a given time period is equal to the product of its speed and time. Mathematically, the distance formula can be written as:
$\Rightarrow $ $Distance=Speed\times time$
Now,
Let the total distance covered by the car be (D).
Let the speed at which the car is moving be (u).
And the total time taken be (t).
Then, our new equation is:
$\Rightarrow D=u\times t$
In the problem, it has been given to us:
$\Rightarrow u=45kmh{{r}^{-1}}$ and,
$\Rightarrow t=0.5hrs$
Then, the total distance travelled (D) can be calculated as:
$\begin{align}
  & \Rightarrow D=45\times 0.5km \\
 & \Rightarrow D=22.5km \\
\end{align}$
Thus, the car has travelled a total distance of $22.5km$ in the West direction.

Note:
In this problem, we saw the application of a very simple concept. So problems like these should be quickly and correctly solved in order to save time when giving an examination. Also, we need to be careful while writing the units in these problems as different units could be given in the problem, so we would need to convert them first.