<span>They are similar because the matter changes in its state...But they are also different because Physical changes have matter that remains the same substance but it is just in a different state and in chemical changes the matter changes completely... Hope this Helps ^-^</span>
Answer: convection
Explanation:
There are three ways in which the heat (thermal energy) transfer occurs:
<u>1. By Conduction</u>, when the transmission is by the direct contact.
<u>2. By Convection</u>, heat transfer in fluids (like water or the air, for example).
<u>3. By Radiation</u>, by the electromagnetic waves (they can travel through any medium and in vacumm)
In this especific case, we will talk about convection, which occurs when the hottest parts of a fluid ascend to the coldest zones, generating a continuous circulation of the fluid (better known as convective current) transmitting heat to the cold zones by decreasing the density caused by the increase in temperature.
This is what happens in Earth, when the convective heat transfer occurs, through the movement of groups of molecules that make up the medium (water and air in this situation) changing with temperature and creating the weather .
Answer:
Explanation:
distance walked
5000 + 3000 + 1000 = 9000 m
time taken to do the walk
9000 m / 1 m/s = 9000 s
magnitude of displacement during the walk
d = √((5000 - 1000)² + 3000²) = 5000 m
direction of displacement
θ = arctan(3000/4000) = 36.869897...°
velocity
v = d/t = 5000 m / 9000 s = 0.5556 m/s 36.87° N of E
Answer:
The farther star will appear 4 times fainter than the star that is near to the observer.
Explanation:
Since it is given that the luminosity of the 2 stars is same thus they radiate the same energy per unit time
Consider a spherical wave front of energy 'E' that leaves both the stars (Both radiate 'E' as they have same luminosity)
This Energy is spread over the whole surface area of sphere Thus when the wave front is at a distance 'r' the energy per unit surface area is given by
For the star that is twice away from the earth the distance is '2r' thus we will receive an energy given by
Hence we sense it as 4 times fainter than the nearer star.