Answer:
a. Disk, 28 thousand light-years from
Explanation:
Since, a galactic disc is a component of disc galaxies, for instance spiral galaxies and lenticular galaxies. It consists of a stellar component and a gaseous component.
Also, the Sun lies within the galactic disk or in other words it is thought to be located in the galactic disk,
The Sun is located about 26,000 light-years away from the centre of the galaxy.
∵ From the given options 28,000 is nearest to 26,000
Hence, the sun is about 28 thousand light-years from the centre of the galaxy.
i.e. OPTION 'a' would be correct.
Answer:
Thickness of Styrofoam insulation is 0.02741 m.
Explanation:
Given that,
Height = 0.25 m
Depth = 0.5 m
Power = 400 W
Temperature = 33°C
We need to calculate the area of Styrofoam
Using formula of area

Put the value into the formula


Inner surface temperature of freezer

Outer surface temperature of freezer

We need to calculate the thickness of Styrofoam insulation
Using Fourier law,


Put the value into the formula


Hence, Thickness of Styrofoam insulation is 0.02741 m.
Answer:

Explanation:
As we know that


also we know that

it is given as


also we can find the magnitude of two vectors as


similarly we have


now we know the formula of dot product as




Answer: 117.6N
Explanation:
By the second Newton's law, we know that:
F = m*a
F = force
m = mass
a = acceleration
We know that in the surface of the Earth, the gravitational acceleration is g = 9.8m/s^2.
Then we just can input that acceleration in the above equation, and also replace m by 12kg, and find that the force due the gravity is:
F = 12kg*9.8m/s^2 = 117.6N