1) 17.1 m/s
2) 17.1 m/s south
Explanation:
1)
The speed of an object is a scalar quantity indicating "how fast" is the object moving, regardless of its direction of motion.
Being a scalar quantity, it has only a magnitude, while it doesn't have a direction.
The speed of an object is given by the formula:
[tex]v=\frac{d}{t}[/tex]
where:
d is the distance covered by the object, which is the total length of the path covered by the object
t is the time taken to cover the distance d
In this problem we have:
[tex]d=740 km =740,000 m[/tex] is the distance covered by the ducks
[tex]t=12 h \cdot 60 \cdot 60 =43,200 s[/tex] is the time taken
Substituting, we find:
[tex]v=\frac{740,000}{43,200}=17.1 m/s[/tex]
2)
The velocity of an object is a vector quantity indicating how fast the object is moving in a certain direction.
Being a vector, velocity has both a magnitude and a direction.
The magnitude of the velocity is given by:
[tex]v=\frac{d}{t}[/tex]
where
d is the displacement, which is the shortest distance in a straight line between the initial position and the final position of motion
t is the time taken for the displacement d to occur
And the direction is equal to the direction of the displacement.
In this problem:
[tex]d=740 km = 740,000 m[/tex] south is the displacement
[tex]t=12 h \cdot 60 \cdot 60 =43,200 s[/tex] is the time taken
Substituting, we find:
[tex]v=\frac{740,000}{43,200}=17.1 m/s[/tex] south
