Answer:
Distance travelled: [tex]10\, \pi[/tex] meters (approximately [tex]31.4[/tex] meters.)
Magnitude of displacement: [tex]20[/tex] meters.
Explanation:
The displacement of an object in a motion is the change in the position, regardless of the path that was taken.
In this question, the position of the particle was initially on one side of the circle, and is now on the other side of the semicircle. If the two positions are joined with a line, that line segment between the two positions would represent a diameter of the circle. Since radius of the circle is [tex]r = 10[/tex] meters, the diameter of the circle would be [tex]d = 2\, r = 20[/tex] meters.
Hence, the magnitude of the displacement of the particle would be the same as the length of the diameter of this circle, [tex]20[/tex] meters.
The distance that an object travelled in a motion is the length of the path that the object has taken. In this question, the path represents an arc which forms one-half of the full circle. Since the circumference of the full circle would be [tex]2\, \pi\, r[/tex], one-half that length would be [tex]\pi\, r = 10\, \pi[/tex] meters.
In other words, the distance travelled in this motion would be [tex]10\, \pi[/tex] meters.