Question

A horse began running due east and covered 25 km in 4.0 hr. What is the average velocity of the horse?
A) 0.16 km/hr due east
B) 6.25 km/hr due east
C) 16 km/hr due east
D) 100 km/hr due east

Answer 1

B) 6.25 km/hr due east 

Answer 2

Answer:

B) $v = 6.25\frac{km}{hr}$ due east

Explanation:

Conceptual analysis

The average speed (v) is defined as the relationship between the displacement (d)  that a body made and the total time (t) it took to perform it and is calculated by the following formula:

$v = \frac{d}{t}$ Formula (1)

v: velocity in m/s

d: Displacement (m)

t: Time (s)

Known data

We know the following data

d = 25 km

t = 4.0 hr

Problem development

We replace data in formula (1):

$v =\frac{25km}{4hr}$

$v = 6.25\frac{km}{hr}$