Answer:
I feel that people hurt the land and are destroying. I think they aren't using the land for the right reasons.
The speed of sound in fresh water is 1482m/s.
It says ocean floor, so we should a little bit more accurate, and use the fact that the speed of sound in salt water (that has no bubbles) is 1560m/s.
speed = distance / time
Therefore Distance = speed x time = 1560 x 3.3 = 5158m
The sonar wave is sent out by the boat, reflected off the seafloor, and then is received back at the boat on the surface. So the distance 5148m is the distance from the boat to the sea bottom and then back up to the boat again.
So the depth of the water is half this distance Depth of water = 5148/2=2574m
Answer:
100m.
Explanation:
Simply put, displacement is how far you've been displaced from your starting location. say you start at 0. You now travel E (assuming East) at 10 m/s for 10 s. Now, let's assume m is meters and s is seconds. you moved east at 10 meters per second for 10 seconds. This means that for each second you moved east, you moved 10 meters. Therefore, your displacement is 100 meters because 10 times 10 is 100. So you would write 100m as your displacement.
Answer:
b. AG, work function=4.74eV
Explanation:
Ultraviolet light starts at the end of the visible light spectrum, where violet light ends:
(wavelength of lowest-energy ultraviolet light)
So, the lowest energy of ultraviolet light can be found by using the formula
where
h is the Planck constant
c is the speed of light
Substituting,
And keeping in mind that
This energy converted into electronvolts is
The work function of a metal is the minimum energy needed to extract a photoelectron from the surface of the metal. Therefore, the metals that exhibit photoelectric effect are the ones whose work function is larger than the energy we found previously, so:
b. AG, work function=4.74eV
Because for all the other metals, visible light will be enough to extract photoelectrons.
