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3. You have three stars. Star A has an apparent magnitude of 7, Star B has an apparent magnitude of 2, and Star C has an apparen

Mrrafil [7]

"Apparent magnitude" means how bright a star looks to
a person on Earth.

-- The star that appears brightest is the one with the
lowest-number apparent magnitude . . . Star-C, at -4 .

-- All of them are visible from Earth, but may require some 'help'.
The dimmest stars visible with good human eyes under dark,
non-polluted skies are those with apparent magnitude around 6.
Stars B and C would be visible to the unaided eye, but Star-A
would require binoculars.
Around here, a few miles outside of the Chicago city limits, we're
lucky to see Magnitude-4 without binoculars.

-- It's not possible to determine which star has the highest luminosity.
The apparent magnitude depends on the star's distance from Earth
as well as its luminosity.
A flashlight 3 feet from your face appears much brighter than any
star, although any star is more luminous than the flashlight.
Distance from you has a lot to do with it.
_____________________________________________

"Absolute magnitude" means how bright each star would appear
to a person on Earth if all stars were at the same distance from us.
(The distance happens to be 32.6 light years.) It only depends on
the star's real luminosity, not on its distance.

-- It's not possible to determine which star appears brightest.
Star-C (absolute -7) would appear brightest if all stars were
equal distances from us. But a flashlight ... which has a huge-
number absolute magnitude because we couldn't see at all from
32.6 light years away ... can appear very bright from 3 feet in
front of your face.

-- They're all visible from Earth, but a star with absolute magnitude
greater than 6 would need binoculars (or better) to be visible.

-- Yes, if you know a star's absolute magnitude, then you know its
luminosity. The lowest-number absolute magnitudes are the ones
that would appear brightest if all stars were the same distance from
us, so they're the stars with the greatest luminosity. From this group,
that's Star-C.

6 0

2 years ago

A student wants to investigate the motion of a ball by conducting two different experiments, as shown in Figure 1 and Figure 2 a

Lelu [443]

It equals to G

^the answer

5 0

2 years ago

A target in a shooting gallery consists of a vertical square wooden board, 0.250 m on a side and with mass 0.750 kg, that pivots

Alenkasestr [34]

Here in this case since there is no torque about the hinge axis for the system of bullet and block then we can say that angular momentum of this system will remain conserved

$L_i = L_f$

$mv \frac{L}{2} = (I_1 + I_2)\omega$

here we will have

L = 0.250 m

v = 385 m/s

m = 1.90 gram

now moment of inertia of the plate will be

$I_1 = \frac{ML^2}{3}$

$I_1 = \frac{0.750 (0.250)^2}{3} = 0.0156 kg m^2$

$I_2 = m(\frac{L}{2})^2 = 0.0019(0.125)^2 = 2.97 \times 10^{-5} kg m^2$

now from above equation

$0.0019 (385)(0.125) = (0.0156 + 2.97 \times 10^{-5})\omega$

$\omega = 5.85 rad/s$

8 0

2 years ago

Assuming the same current is running through two separate coils, why is it easier to thrust a magnet into a wire coil with one l

s2008m [1.1K]

The magnetic field strength in a coil is directly proportional to the number of turns, or loops, in the coil.
Therefore, when there are four loops instead of one, the magnetic field strength has increased four times, making it harder to push the magnet in.

6 0

2 years ago

Read 2 more answers

Two uniform, solid cylinders of radius R and total mass M are connected along their common axis by a short, light rod and rest o

sveta [45]

Explanation:

A) To prove the motion of the center of mass of the cylinders is simple harmonic:

System diagram for given situation is shown in attached Fig. 1

We can prove the motion of the center of mass of the cylinders is simple harmonic if

$a_{x} = -\omega^{2} x$