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

Hint: 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.