A body has centripetal acceleration with magnitude <em>a</em> such that
<em>a</em> = <em>v</em> ² / <em>R</em>
where <em>v</em> is the body's tangential speed and <em>R</em> is the radius of the circular path the body takes.
Convert the child's angular speed <em>ω</em> into linear/tangential speed. Assume angular speed is measured in rad/s and tangential speed in m/s. For every 2<em>π</em> rad that he revolves around his mother, the child travels a distance of 2<em>πR</em> m, so that
<em>ω</em> = (<em>ω</em> rad/s) • (2<em>πR</em>/(2<em>π</em>) m/rad) = <em>Rω</em> = <em>v</em>
Then the child's acceleration is
<em>a</em> = (<em>Rω</em>)² / <em>R</em> = <em>Rω</em> ²
When the mother pulls her arms in, the distance <em>R</em> gets halved and changes to <em>R</em>/2, so that the child's new acceleration is
<em>a</em> = (<em>R</em>/2 • <em>ω</em>)² / (<em>R</em>/2) = (1/4 • (<em>Rω</em>)²) / (1/2 • <em>R</em>) = 1/2 <em>Rω</em> ²
so the child's centripetal acceleration decreases by a factor of 2.
Answer:
0.30 m/s²
Explanation:
Given:
v₀ = 0.2 m/s
v = 1.6 m/s
t = 4.7 s
Find: a
a = (v − v₀) / t
a = (1.6 m/s − 0.2 m/s) / 4.7 s
a = 0.30 m/s²
Basically velocity is a vector quantity and is specified in m/s (meters/second). Speed is the distance traveled by an object where as, velocity is distance traveled by an object per unit time in a particular direction. Speed is a scalar quantity where as velocity is a vector quantity
Hi!
Answer D would be the best option.
During the period of adolescence, which is generally between 13-19, the individual goes through a transitional period which is characterized by changes in emotional, physical and mental capacities.
These changes consequently result in the adolescents' desire to be more independent, and to govern their lives as how they deem more fitting, which results in the rebellious nature in the individual.
The other options include characteristics that MAY be seen in individuals, but is not a defining characteristic of adolescence and is not very common.
Hope this helps.
