Question

You can enter units that are combinations of units with prefixes. However, you must maintain the same unit system given in the problem. For example, this question uses the SI unit system, Therefore an answer in U.S customary units, such as miles per hour would not be accepted as correct. A car traveling with constant speed travels 150 km in 7200 s.

What is the speed of the car?

Express the speed to two significant figures and include the appropriate units.

Answer 1

Answer:

750 km/h

Explanation:

Speed is the time rate of change of distance. Mathematically, it is given as:

$Speed = \frac{distance}{time}$

The car travels a distance of 150 km.

It travels for 7200 s.

The unit of speed is kilometre per hour (km/h) or metre per second (m/s). This means that to solve this we have to either convert the distance to metres or the time to hours.

Let us convert time to hours.

1 hour = 3600 seconds, therefore:

Time = $\frac{7200}{3600}$ = 2 hours

The speed will then be:

Speed = $\frac{150}{2} = 75 km/hr$