The second law states that the total entropy can never decrese over time for an isolated system
Answer:
The second material's index of refraction is 1.17.
Explanation:
Given that,
Refractive index of the material, n = 1.29
Critical angle is 65.9 degrees.
We need to find the second material's index of refraction. We know that at critical angle of incidence, angle of refraction is equal to 90 degrees. Using Snell's law as:
So, the second material's index of refraction is 1.17.
A job is done slowly and an identical job is done quickly then they require same amount of work, but different amounts of power.
Answer: Option B
<u>Explanation:
</u>
Work done is the amount of force required to displace an object from its original position. So as force depends on mass of the object. The work will remain constant for doing a particular job related to same object. But power defines the work done per unit time.
So if power is increased for a given work means the time required to do that work is reduced. So if a particular work has to be performed on a same object then by manipulating the power we can change the time taken to complete that job.
So in this case for the identical job, one is completed slowly while other has been done quickly. This indicates that they required same amount of work as the kind of job is same but different amount of power depending on which the work is done fast or slowly.
Answer:
21.67 m/s²
Explanation:
From the question given above, the following data were obtained:
Velocity (v) = 49.7 m/s
Radius (r) = 114 m
Centripetal acceleration (a) =?
The centripetal acceleration can be obtained by using the following formula:
a = v²/r
a = 49.7² / 114
a = 2470.09 / 114
a = 21.67 m/s²
Therefore, the centripetal acceleration of the car is 21.67 m/s²
Complete Question
One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. Having recently studied optics in your physics class, you're not too surprised to see that the patch of light seems to be a circular diffraction pattern. It appears that the central maximum is about 2 cm across, and you estimate that the distance from the window shade to the wall is about 5 m.
Required:
Estimate the diameter of the pinhole.
Answer:
The diameter is
Explanation:
From the question we are told that
The central maxima is
The distance from the window shade is
The average wavelength of the sun is mathematically evaluated as
Generally the visible light spectrum has a wavelength range between 400 nm to 700 nm
So the initial wavelength of the sun is
and the final wavelength is
Substituting this into the above equation
The diameter is evaluated as
substituting values