Explanation:
For, heating purposes more the quantity of water more will be the heating. Clearly, underground heating would have more water and hence, it will have edge over the water heater system.
Moreover, for things at the same temperature, the thing with more molecules has more total kinetic energy (thermal energy) than the thing with fewer molecules. The groundwater heating system uses heat from the heat stored naturally in groundwater or aquifers. Thus, saving the cost of power required to heat in normal water heater.
The initial velocity of go-kart is 2.5 m/s.
<u>Explanation:</u>
Here, the uniform acceleration of go-kart is given as 0.5 m/s². Also the time required by it to stop is also given as 5 s. As acceleration is the measure of change in velocity per unit time.
In this case, the velocity should be changed from a value to zero to come to rest. So the initial velocity will be positive value and final velocity is zero.
As we know the values of acceleration, final velocity and time, the initial velocity can be easily determined as follows.

Since, final velocity is zero, acceleration is 0.5 m/s² and time is 5 s, then,

Initial velocity = 0.5 × 5 = 2.5 m/s.
So the initial velocity of go-kart is 2.5 m/s.
Light intensity is the "amount of light given off a light source." Also, is the measure the wavelength of the amount of light given off by a light source.
Hope this helps.
20/45=0.4*100= 44.4 so the answer is..................................................
Answer: 44.4%
At the present time, the only way we know of that light can get shifted
toward the blue end of the spectrum is the Doppler effect ... wavelengths
appear shorter than they should be when the source is moving toward us.
IF that's true in the case of the Andromeda galaxy, it means the galaxy is
moving toward us.
We use the same reasoning to conclude that all the galaxies whose light is red-shifted are moving away from us. That includes the vast majority of all galaxies that we can see, and it strongly supports the theory of the big bang
and the expanding universe.
If somebody ever comes along and discovers a DIFFERENT way that light
can get shifted to new, longer or shorter wavelengths, then pretty much all
of modern Cosmology will be out the window. There's a lot riding on the
Doppler effect !