Question

A plane could fly at an average speed of $694m{s^{ - 1}}$ . Calculate how long it would take the plane to fly around the world (which is $4.00 \times {10^7}m$ )?

Answer 1

It is known that the distance traversed by a body is the product of its velocity and time taken by the body to traverse the distance. Mathematical expression for the distance traversed by a body moving with a uniform speed is given by, $s = vt$ where, is the velocity of the body and is the time taken by the body to cover the distance.

Complete step by step answer:
We have been given here that a plane flies with an average speed of $694m{s^{ - 1}}$ . We have to find the time taken by the plane to fly around the world. Now we know that the distance traversed by a body is the product of its velocity and time taken by the body to traverse the distance. Mathematical expression for the distance traversed by a body moving with a uniform speed is given by, $s = vt$ where, is the velocity of the body and is the time taken by the body to cover the distance.
So, the time taken by plane to fly around the world will be, $t = \dfrac{s}{v}$ .
We have given here the distance traveled to fly around the world is $s = 4.00 \times {10^7}m$ and the average speed of the plane is, $v = 694m{s^{ - 1}}$ .
So, the time taken by plane to fly around the world will be,
$t = \dfrac{{4.00 \times {{10}^7}}}{{694}}s$
$t = 57.63 \times {10^3}s$
Now, we know,
$1hour = 3600\operatorname{s}$ .
So, time taken by the plane will be,
$\dfrac{{57.63 \times {{10}^3}}}{{3600}}hour$
That will be equal to $16.01hour$ .
So, to fly around the world with an average speed of $694m{s^{ - 1}}$ the plane will take $16.01hour$.

Note:
The average speed of a body is calculated as the total distance travelled by the time taken. In mathematical expression we can write the average speed of a body is, ${v_{avg}} = \dfrac{{\sum {{d_i}} }}{{\sum {{t_i}} }}$ . Where $\sum {{d_i}} = d$ is the total distance and ${t_i}$ is the time taken to travel ${d_i}$ distance.