The echo is weaker than the original sound since the echo has a smaller amplitude than the original sound because sound spreads and its intensity decreases with distance. For example, when the sound from a speaker is heard and is compared to its echo, the echo heard has a lower amplitude than the actual sound.
Answer: The handle of a frying pan on the stove
Explanation: Convection is the heat transfer done by the movement of a fluid, or the molecules on it. This can happen by the change on density from fluids, when a fluid tempeture rise, it expands, rising his volumen and decreasing his density. When this happens the fluid becomes lighter, so it moves.
The handle of a frying pan gets hotter but no molecular movement is done. It is between the same material there is a energy transfer from the source to the rest of the pan. This is called Conduction.
Answer:
v = 3.24 m/s
Explanation:
Since we don't have time, we can use the formula;
(Final distance - initial distance)/time = (initial velocity + final velocity)/2
Thus;
(x_f - x_i)/t = ½(v_xi + v_xf)
We are given;
x_i = 0 m
x_f = 5 m
v_xi = 0 m/s
v_xf = 5 m/s
Thus, plugging in the relevant values;
(5 - 0)/t = (0 + 5)/2
5/t = 5/2
t = 2 s
Using Newton's first law of motion, we can find the acceleration.
v = u + at
Applying to this question;
5 = 0 + a(2)
5 = 2a
a = 5/2
a = 2.5 m/s²
To get the speed, in m/s, of the block when it had traveled only 2.1 m from the top, we will use the formula;
v² = u² + 2as
v² = 0² + 2(2.5 × 2.1)
v² = 10.5
v = √10.5
v = 3.24 m/s
The answer is counter clockwise relative to the polaris. The polaris, also known as northern star would seem a bit more stable on the night sky as the point of vision is up north, the stars however around this would look as if it was rotating, left to right but since the earth is round in shape it follows a circular pattern.
Answer:
2.25 %
Explanation:
65-95-99.7 is a rule to remember the precentages that lies around the mean.
at the range of mean (
) plus or minus one standard deviation (
), ![P([\mu-\sigma \leq X \leq \mu+\sigma])\approx 68.3%](https://tex.z-dn.net/?f=P%28%5B%5Cmu-%5Csigma%20%5Cleq%20X%20%5Cleq%20%5Cmu%2B%5Csigma%5D%29%5Capprox%2068.3%25)
at the range of mean plus or minus two standard deviation, ![P([\mu -2\sigma \leq X \leq \mu+2\sigma])\approx 95.5%](https://tex.z-dn.net/?f=P%28%5B%5Cmu%20-2%5Csigma%20%5Cleq%20X%20%5Cleq%20%5Cmu%2B2%5Csigma%5D%29%5Capprox%2095.5%25)
at the range of mean plus or minus three standard deviation, ![P([\mu - 3\sigma\leq X \leq \mu+3\sigma])\approx 99.7%](https://tex.z-dn.net/?f=P%28%5B%5Cmu%20-%203%5Csigma%5Cleq%20X%20%5Cleq%20%5Cmu%2B3%5Csigma%5D%29%5Capprox%2099.7%25)
So, note that they are asking about the probability that it is greater than 0.32, that is the mean (0.3) plus two times the standard deviation (0.1) (
)
So we know that the 95.5% is between 
and 
, hence approximately the 4.5% (100%-95.5%) is greater than 0.32 or less than 0.28. But half (4.5%/2=2.25%) is greater than 0.32 and the other half is less than 0.28.
So 
