Answer:
This is due to a relative decrease in atmospheric pressure in high places.
Explanation:
Given that atmospheric pressure decreases at the higher point or ground, this reduced atmospheric pressure, however, will be unable to contain the Mercury in the barometer tube.
Therefore, at the top of the mountain where the air pressure is low, the barometer reading ultimately goes down.
Hence, the level of mercury falls in a barometer while taking it to a mountain "due to a relative decrease in atmospheric pressure in high places."
Given:
Work done, W = 5 J
Initial energy = 8J
Final energy = 30J
Let's determine if the work done have a positive or nrgative value.
Appy the equation for the first lae of thermodynamics:
Where:
U is the change in internal energy
Q is the added heat
W is the work done
To find the work done here, we have:
Rewrite the formula for W
Where:
ΔU = 30J - 8J = 22J
Q = 5J
Thus, we have:
Therefore, the work done here is -17J.
This means the work done in this scenario has a negative value.
ANSWER:
The work done in this scenario has a negative value
Answer:
Liquid's index of refraction, n₁ = 1.27
Explanation:
It is given that,
The critical angle for a liquid in air is, 
We have to find the refractive index of the liquid. Critical angle of a liquid is defined as the angle of incidence in denser medium for which the angle of refraction is 90°.
Using Snell's law as :
Here, 
Where
n₂ = Refractive index of air = 1
n₁ = refractive index of liquid
So,
n₁ = 1.269
or n₁ = 1.27
Hence, the refractive index of liquid is 1.27
Answer:
the answer is A. A school crossing guard raises a stop sign that weigh 10 N
Answer: Choice A) 0.44 miles
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Work Shown:
1 hour = 60 minutes
1 minute = 60 seconds
1 hour = 60*60 = 3600 seconds
40 seconds = 40*(1/3600) = 40/3600 = 1/90 hours
The car travels 1/90 of an hour. Let t = 1/90.
The initial velocity is vi = 30 mph.
The final velocity is vf = 50 mph.
Apply one of the kinematics equations as given below.
x = distance traveled
x = 0.5*(vi+vf)*t
x = 0.5*(30+50)*(1/90)
x = 0.44444444444444 which is approximate
x = 0.44
The car traveled roughly 0.44 miles. This matches with choice A.
I'm assuming choice A is supposed to say 0.44 instead of 0.442; otherwise, I think your teacher made a typo by putting that 2 in there. Each of the other answer choices are accurate to 2 decimal places, so it would make sense that choice A is also accurate to 2 decimal places as well.
If 0.442 was intended by your teacher, and it's not a typo, then the answer would be E) None of the choices given.
