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Room temperature is approximately 20°C.
We can automatically eliminate choices B and D since they are not equal to 20°C.
Since some choices use the Kelvin scale, we can convert from Celsius to Kelvin using a simple formula:
K = C° + 273
Find room temperature in degrees <u>Kelvin</u>:
K = 20° + 273
K = 293°
Thus, the correct choice would be <u>C. 293K.</u>
Answer:
Add Ff from Fa
Explanation:
Fnet = sum of all force
horizontal net force = Ff + Fa
The work done by the force is 47.1 J
Explanation:
The work done by a force in moving an object is given by
(1)
where
F is the magnitude of the force
d is the distance covered by the object
is the angle between the direction of the force and the motion of the object
In this problem, the force applied to the object is
F = 3.0 N
This force is always tangential to the track: this means that at every instant, the force is parallel to the motion of the object, so

And the distance covered is equal to the circumference of the circle, which is:

where r = 2.5 m is the radius.
Now we can substitute into eq.(1) to find the work done:

Learn more about work:
brainly.com/question/6763771
brainly.com/question/6443626
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Answer:
Its length is measured to be 0.5 m
Explanation:
From theory of relativity (mass variation), we know that:
m = mo/√(1-v²/c²)
Where, m = relative mass
and, mo = rest mass
The momentum of stick while moving, will be:
P = mv
but, it is given in the form of rest mass as:
P = 2(mo)v
thus, by comparison;
2(mo)v = mv
using value of m from theory of relativity;
2(mo)v = (mo)v/√(1-v²/c²)
√(1-v²/c²) = 1/2 ______ eqn(1)
Now, for relativistic length (L), we have the formula from same theory of relativity;
L = (Lo)√(1-v²/c²)
The rest length (Lo) of meter stick is 1 m, and the remaining term on right side √(1-v²/c²), known as Lorentz Factor, can be given by eqn (1), as equal to 1/2.
Thus,
L = (1 m)(1/2)
<u>L = 0.5 m</u>
"The process used by scientific investigations is the scientific method. This involves making an observation, stating a question, formulating a hypothesis, conducting an experiment and analyzing the results to form a conclusion. "
I would most likely go with B. but im not 100% sure