Answer:
37500 J
Explanation:
Law of conservation of energy: Its states that energy can neither be created nor destroyed but it can be transformed from one form to another.
Applying the law of conservation of energy.
The change in kinetic energy for the truck = Net work done by the truck skids
ΔK.E = F×d.................... Equation 1
Where ΔK.E = Change in kinetic energy, F = Force, d = distant.
Given: F = 1500 N, d = 25 m
Substitute these values into equation 1
ΔK.E = 1500×25
ΔK.E = 37500 J
Answer:
As the phase changes occur, the freedom of motion of the particles increases
Explanation:
As the phase changes occur from solid to gas, the freedom of motion of the particles increases
At the solid state (let's say ice), the molecules of the solid are tightly packed and they are unable to move freely. When heat is applied to the state of the solid, ice it melts and the molecules of the solid gains kinetic energy and therefore tends to shift away from their mean fixed position due to heat. This kinetic energy possesses by this molecules allow them to move freely (energy due to motion). When further heat is applied to the liquid (above the boiling point), the molecules of the water vapourizes(turns to gas) and this molecules gain more kinetic energy more than they do in liquid state and were able to move freely more than in liquid. This shows that the freedom of the particles (molecules) increase with change in state from solid to gas.
Wavelength = (speed) / (frequency)
so in order to answer this question, we need the speed of sound.
Without using my precious time to go look it up, I'm guessing that
the speed of sound at STP is roughly 343 m/s .
If that estimate is accurate, then
Wavelength = (343 m/s) / (440 /s) = 0.78 meter .
Choice-#2 is much closer to this result than any of the others,
so choice-2 must be it.
Actually, we can 'reverse engineer' Choice-#2 and find the number
it uses for the speed of sound.
Speed = (wavelength) x (frequency)
= (0.75 m) x (440 /s) = 330 m/s .
The author of the question used 330 m/s for the speed of sound.
Complete question:
standard 14.16-inch (0.360-meter) computer monitor is 1024 pixels wide and 768 pixels tall. Each pixel is a square approximately 281 micrometers on each side. Up close, you can see the individual pixels, but from a distance they appear to blend together and form the image on the screen.
A) If the maximum distance between the screen and your eyes at which you can just barely resolve two adjacent pixels is 1.30 meters, what is the effective diameter d of your pupil? Assume that the resolvability is diffraction-limited. Furthermore, 550*10^-9m as a characteristic optical wavelength. Express your answer in millimeters to three significant figures.
B.) Assuming that the screen is sufficiently bright, at what distance can you no longer resolve two pixels on diagonally opposite corners of the screen, so that the entire screen looks like a single spot? Note that the size (0.360 meters) quoted for a monitor is the length of the diagonal. Express your answer in meters to three significant figures.
Answer:
a) 3.1mm
b) 1663m
Explanation:
Given:
Screen resolution =1024*768 pixel at approximately 281m each
a) Let's take sin∅ =
Solving for d we have:
d = 3.10mm
b) given:
y = 0.360m
We now have d= 3.1mm
To find L, we use:
L = 1663m
NEG: As tech gets better and better, all the old models usually just get tossed increasing all the landfill stuff that won't ever really decompose.
POS: a large reduction of paper usage, and multi functioning devices.