Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores. Aside from our sun, the dots of light we see in the sky are all light-years from Earth. They are the building blocks of galaxies, of which there are billions in the universe. It’s impossible to know how many stars exist, but astronomers estimate that in our Milky Way galaxy alone, there are about 300 billion.
First question: 800J
Second question: 20.4m
The momentum of the
x-ray photon is p = h/lambda . Lambda is the wavelength (0.30nm=3x10^(-9)m) and
h is Planck's constant,(h=6.62607004 × 10-34<span> m2 kg / s).The
momentum is: 2.2 x 10^(-25).</span>
The momentum can be calculated
also as: p=mv, where m is the mass of the electron and v is the speed.
So v=p/m,p is known,and
also the mass of the electron (m=9.10938356 × 10-31<span> kilograms).</span>
v=2.2 x 10^(-25)/9.10938356
× 10-31<span> kilograms=0.24 x 10^6 m/s</span>
Answer:
Explanation:
Force Mass * acceleration
F = ma
a = F/m
Sum of force = 16.3N - 15.8N = 0.5N
Mass = 0.62kg
Substitute
a = 0.5/ * 0.62
a = 0.81m/s²
The acceleration of the toy is 0.81m/s²
<span>3598 seconds
The orbital period of a satellite is
u=GM
p = sqrt((4*pi/u)*a^3)
Where
p = period
u = standard gravitational parameter which is GM (gravitational constant multiplied by planet mass). This is a much better figure to use than GM because we know u to a higher level of precision than we know either G or M. After all, we can calculate it from observations of satellites. To illustrate the difference, we know GM for Mars to within 7 significant figures. However, we only know G to within 4 digits.
a = semi-major axis of orbit.
Since we haven't been given u, but instead have been given the much more inferior value of M, let's calculate u from the gravitational constant and M. So
u = 6.674x10^-11 m^3/(kg s^2) * 6.485x10^23 kg = 4.3281x10^13 m^3/s^2
The semi-major axis of the orbit is the altitude of the satellite plus the radius of the planet. So
150000 m + 3.396x10^6 m = 3.546x10^6 m
Substitute the known values into the equation for the period. So
p = sqrt((4 * pi / u) * a^3)
p = sqrt((4 * 3.14159 / 4.3281x10^13 m^3/s^2) * (3.546x10^6 m)^3)
p = sqrt((12.56636 / 4.3281x10^13 m^3/s^2) * 4.458782x10^19 m^3)
p = sqrt(2.9034357x10^-13 s^2/m^3 * 4.458782x10^19 m^3)
p = sqrt(1.2945785x10^7 s^2)
p = 3598.025212 s
Rounding to 4 significant figures, gives us 3598 seconds.</span>
