All categories

2 years ago

11. Reflecting telescopes are popular because they're _______ than a refracting telescope.

2 answers:

4 0

I do not know what the school expects as an answer, but advantage of reflecting telescopes is that there is only one major reflecting surface, so it is quite easy to create a 6 or 8 inch telescope by an amateur, after adding on a prism and an eyepiece. (a microscope eyepiece could be used).
MY answer would be "easier to build". (it still takes tens of hours to grind and polish the single plane surface to a parabolic surface).

Electromagnetic waves all have the same velocity in the same medium. However, since frequencies vary widely, so do wavelengths.

lyudmila [28]2 years ago

4 0

for 11. the answer is they are D. easier to build. hope i helped (:

You might be interested in

What is the magnitude of the electric field at the point if the electric potential in the region is given by V 2.00xyz2, where V

Hatshy [7]

Answer:

Electric field at a point ( x , y , z) is $E=-2yz^2-2xz^2-4xyz$ .

Explanation:

Given :

Electric potential in the region is , $V = 2xyz^2\ .$

We need to find the electric field .

We know , electric field , $E=-\dfrac{dV}{dr}$ { Here r is distance }

In coordinate system ,

$E=-\dfrac{dV}{\delta x }-\dfrac{dV}{\delta y }-\dfrac{dV}{\delta z }$ { $\delta$ is partial derivative }

Putting all values we get ,

$E=-\dfrac{2xyz^2}{\delta x }-\dfrac{2xyz^2}{\delta y }-\dfrac{2xyz^2}{\delta z }\\\\E=-2yz^2-2xz^2-4xyz$

Hence , this is the required solution.

3 0

2 years ago

The heater element of a particular 120-V toaster is a 8.9-m length of nichrome wire, whose diameter is 0.86 mm. The resistivity

AleksAgata [21]

Answer:

Power, P = 722.96 watts

Explanation:

It is given that,

Voltage, V = 120 V

Length of nichrome wire, l = 8.9 m

Diameter of wire, d = 0.86 mm

Radius of wire, r = 0.43 mm = 0.00043 m

Resistivity of wire, $\rho=1.3\times 10^{-6}\ \Omega-m$

We need to find the power drawn by this heater. Power is given by :

$P=\dfrac{V^2}{R}$

And, $R=\rho\dfrac{l}{A}$

$P=\dfrac{V^2\times A}{\rho\times l}$

$P=\dfrac{120^2\times \pi (0.00043)^2}{1.3\times 10^{-6}\times 8.9}$

P = 722.96 watts

So, the power drawn by this heater element is 722.96 watts. Hence, this is the required solution.

3 0

2 years ago

You are going to speak to a group of your peers on the dangers of drinking and driving. As you prepare your talk, you need to co

enyata [817]

Teens drink mostly because the people/media around them tell them its "cool" and to be liked you have to drink, or "why miss out on the fun?" "Are you scared?" They are pressured into the idea that if they want to be cool or liked, they need to drink.
I'm not in Florida, so I wouldn't know your specific laws, but I know that driving under the influence is pretty much illegal in every state, and you will have consequences if you are caught.
Hope this helps!

3 0

2 years ago

Suppose the stone is thrown at an angle of 39.0° below the horizontal from the same building as in the Example above. If it stri

Anni [7]

Suppose the stone is thrown at an angle of 39.0° below the horizontal from the same building as in the Example above. If it strikes the ground 47.8 m away, find the following. (Hint: For part (a), use the equation for the x-displacement to eliminate v0t from the equation for the y-displacement.)(a) the time of flight sThe x coordinate as a function of time is x(t) = vcos(39.0)t, so the initial speed is v0 = Δx/(cos 39.0Δt), where Δx = 47.8 and Δt is the time of flight. Insert this into your equation for y(t) and solve for the time of flight. Note that the answer should be smaller than 3.16227766016838, since the stone is thrown down (and to the right).(b) the initial speed m/s(c) the speed and angle of the velocity vector with respect to the horizontal at impactspeed m/sangle °

5 0

2 years ago

I am currently studying about spectrums, difraction Gratings, and many other spectrum. So my question is: What should the Spectr

saveliy_v [14]

The spectrum of light from the moon should very strongly resemble the spectrum of sunlight. The reason is that any light from the moon started out from the sun. Any difference in their spectra is only due to the moon absorbing more of some wavelengths and less of others. But since the moon appears colorless gray, we don't expect any particular colors to be strongly absorbed, otherwise the moon would look to be the colors of the light that's left.

3 0

2 years ago