Q1PE - College Physics (Urone)

Question

The speed limit on some interstate highways is roughly  100 km/h . (a) What is this in meters per second? (b) How many miles per hour is this?

Step-by-Step Solution

Answer

The speed of any object is referred to as the distance covered by a body in a given time period.

Velocity is the rate of change of distance with respect to time.

Step 1: Defining velocity

The pace at which a body's distance changes in relation to time is referred to as its velocity. Its SI equivalent is  m/s.

Given data

The speed limit  $\mathrm{v}=100 \mathrm{km}/\mathrm{h}$.

Step 2: (a) Explanation of velocity in meters per second

Write the equation for velocity.

$$\begin{gathered} \mathrm{v}=\left(100\frac{\mathrm{km}}{\mathrm{h}}\right)\left(\frac{1000 \mathrm{m}}{3600 \mathrm{s}}\right) \\ =27.78 \mathrm{m}/\mathrm{s} \end{gathered}$$

Step 3: (b) Explanation of velocity in miles per hour

As you know,-

$1 \mathrm{km}=0.621371 \mathrm{miles}$

Write the equation for velocity.

$$\begin{gathered} \mathrm{v}=\left(100\frac{\mathrm{km}}{\mathrm{h}}\right)\left(0.6214 \mathrm{miles}\right) \\ =62.14 \mathrm{miles}/\mathrm{h} \end{gathered}$$

Step 4: Conclusion

Hence, the velocity in meter per second is $27.78 \mathrm{m}/\mathrm{s}$  and in miles per hour is  $62.14 \mathrm{miles}/\mathrm{h}$.