Answer:
96%
Explanation
Let A the total area of the galaxy, is modeled as a disc:
A = πR^2 = π (25 kpc)^2
And let a be the area that astronomers are able to see:
a = πr^2 = π(5 kpc)^2
The percentage that can be seen is equal to 100 times the ratio of the areas, of the galaxy and the "visible" part:
P = 100 a/A = (5/25)^2 = 100/25 = 4%
Therefore, the percentage of the galaxy not included, i.e. not seen is:
(100-4)% = 96%
Answer:
Yes, a sled has inertia while sitting still.
Explanation:
From Newton's law of inertia, an object at rest will remain at rest unless it is acted upon by an external force. The reason the object will remain at rest unless an external force acts is because of inertia. Inertia means the resistance of an object to motion.
Thus, a sled hammer at rest will remain at rest unless it is acted upon by an external force. So we can conclude that it has Inertia.
They can fight the infection but not the disease
Answer:
Explanation:
Given:
- thickness of the base of the kettle,
- radius of the base of the kettle,
- temperature of the top surface of the kettle base,
- rate of heat transfer through the kettle to boil water,
- We have the latent heat vaporization of water,
- and thermal conductivity of aluminium,
<u>So, the heat rate:</u>
<u>From the Fourier's law of conduction we have:</u>
where:
area of the surface through which conduction occurs
temperature of the bottom surface
is the temperature of the bottom of the base surface of the kettle.
