Q7PE - College Physics (Urone)

Question

The North American and European continents are moving apart at a rate of about $\mathbf{3}\mathbf{\text{\hspace{0.17em}cm/y}}$. At this rate how long will it take them to drift $\mathbf{500}\mathbf{km}$ farther apart than they are at present?

Step-by-Step Solution

Answer

$16.6\times {10}^6\text{\hspace{0.17em}years}$

Step 1: Given Data

• Speed of the drift  $=3\text{\hspace{0.17em}cm/y}=0.03\times {10}^{-3}\text{\hspace{0.17em}km/y}$.
• Distance of the drift = 500 km.

Step 2: Speed of the drift

Normally speed is directly proportional to the distance and is inversely proportional to the time taken to cover that distance.

It is a scalar quantity. Speed distance and time are interrelated to each other.

The time after they are 500 km apart can be calculated as:

 $\text{Time}=\frac{\text{Distance}}{\text{Speed}}$

Substituting the values in the above expression, we get:

$\begin{array}{l}\mathrm{T}=\frac{500\text{\hspace{0.17em}km}}{0.03\times {10}^{-3}\text{\hspace{0.17em}km/y}}\\ \mathrm{T}=16,666,666.66\text{\hspace{0.17em}y}\end{array}$

Hence it will take them  $\mathbf{16}.\mathbf{6}\mathbf{x}{\mathbf{10}}^6\mathbf{y}$ to be $\mathbf{\text{500\hspace{0.17em}km}}$  apart from each other.