Assuming it starts at rest, the roller coaster only has potential energy at the top of the hill, which is
When it reaches the bottom, its potential energy will have converted to kinetic energy,
where 
is its velocity at that point. By the law of conservation of energy, assuming no loss of energy due to other sources (e.g. sound, heat), we have
Answer:
a. 37.75°
b. 6.21 m
Explanation:
a. The horizontal force acting on a pendulum bob is given as:
F = mgsinθ
where m = mass of bob
g = acceleration due to gravity
θ = angle string makes with the vertical or angle of displacement
Making θ subject of formula, we have:
θ = 
θ = 
θ = 37.75°
The maximum angle of displacement is 37.75°
b. Period of a pendulum is given as:
where L = length of string
Therefore, making L subject of formula:
The string holding the pendulum has to be 6.21 m long.
Answer:
2.01
Explanation:
First, we need to find the centripetal acceleration.
We're given that the merry go round rotates 1 revolution in 2.09 seconds. Converting to rpm, we know that it rotates 30 revolution per minute
Now this speed gotten in rpm will be converted to m/s, to ease the calculation
30 rpm = πdN/60 m/s
30 rpm = (3.142 * 4 * 30)/60
30 rpm = 377.04/60
30 rpm = 6.284 m/s
a(c) = v²/r
a(c) = 6.284²/2
a(c) = 39.49 / 2
a(c) = 19.74 m/s²
F = ma
F = 50 * 19.74
F = 987 N
Also, Normal Force, F(n) =
F(n) = mg
F(n) = 50 * 9.81
F(n) = 490.5
We then use this to find the coefficient of static friction, μ
μ = F/F(n)
μ = 987 / 490.5
μ = 2.01
What does the psychology workforce look like? In July, APA's Center for Workforce Studies (CWS) released a report to address that question. The report paints a picture of demographic trends in the field from 2005 to 2013, using data from the U.S. Census Bureau's annual American Community Survey.
Though the report paints that picture in relatively broad brushstrokes, it provides an important first step toward a more complete understanding of psychology's workforce. Precise workforce data help policymakers, educators and the public understand the range of psychology's impact on society and can help determine the resources necessary to support them, says Ronald Rozensky, PhD, a professor of clinical and health psychology at the University of Florida and a longtime advocate of workforce analysis.
"Accurate workforce data are really important to use when advocating for education, training, scientific funding and reimbursement for practice," he says.
The new report analyzed data from the approximately 83,000 individuals who listed their occupation as "psychologist" and reported having a professional degree (such as an MD, DDS or JD) or doctoral degree (such as a PhD or EdD) in any field. From 2005 to 2013, the supply of active psychologists remained fairly stable, the authors found, with enough new psychologists entering the field to compensate for an increase in the number of retired psychologists over that span.
That workforce was not evenly distributed, however. California, New York and Pennsylvania have the largest numbers of active psychologists. In fact, those three states together account for a third of the workforce. Western and Southern states tended to have the lowest numbers of active psychologists.
Answer:
<h2>7.5 kg</h2>
Explanation:
The mass of the train can be found by using the formula
k is the kinetic energy
v is the velocity
From the question we have
We have the final answer as
<h3>7.5 kg</h3>
Hope this helps you
