Answer:
0.71 m/s
Explanation:
We find the time it takes the stone to hit the water.
Using y = ut - 1/2gt² where y = height of bridge, u = initial speed of stone = 0 m/s, g = acceleration due to gravity = -9.8 m/s² (negative since it is directed downwards)and t = time it takes the stone to hit the water surface.
So, substituting the values of the variables into the equation, we have
y = ut - 1/2gt²
82.2 m = (0m/s)t - 1/2( -9.8 m/s²)t²
82.2 m = 0 + (4.9 m/s²)t²
82.2 m = (4.9 m/s²)t²
t² = 82.2 m/4.9 m/s²
t² = 16.78 s²
t = √16.78 s²
t = 4.1 s
This is also the time it takes the raft to move from 5.04 m before the bridge to 2.13 m before the bridge. So, the distance moved by the raft in time t = 4.1 s is 5.04 m - 2.13 m = 2.91 m.
Since speed = distance/time, the raft's speed v = 2.91 m/4.1 s = 0.71 m/s
Hertz Pitch and frequency
Ball 4 because the higher the elevation is the greater the potential energy it has
Answer:
Minimum thickness will be 100 nm
Explanation:
We have given refractive index is n = 1.5
Wavelength of the light incidence 
= 600 nm
We have to find the smallest thickness of the film so that there will be minimum light reflect
For minimum thickness of non reflecting film
, here t is thickness, is wavelength and n is refractive index
Putting all values 
So minimum thickness will be 100 nm
"Accuracy" would be the best option from the list regarding the property of a measurement that is best estimated from the percent error, since the higher the error is the lower the accuracy.
Explanation:
When taking scientific measurements, it's vital to be each correct and precise. Accuracy represents however shut a mensuration involves its true price. This can be vital as a result of unhealthy instrumentality, poor processing or human error will result in inaccurate results that aren't terribly getting ready to the reality.
