A single polarizer will stop 50% of the incoming light.
Explanation:
A wave having a frequency of 200 Hz means that 200 such waves pass through a point per second.
Answer:
a.3Hz
b.0.0034m
Explanation:
First, we know the flute is an open pipe, because open pipe as both end open and a close organ pipe as only one end close.
The formula relating the length and he frequency is giving as
.
a.we first determine the length of the flute at the fundamental frequency i.e when <em>n</em>=1 and when the speed is in the 342m/s
Hence from
.
since the value of the length will remain constant, we now use the value to determine the frequency when the air becomes hotter and the speed becomes 345m/s.
![f=\frac{nv}{2l} \\f=\frac{345}{2*0.389}\\f=443.4Hz](https://tex.z-dn.net/?f=f%3D%5Cfrac%7Bnv%7D%7B2l%7D%20%5C%5Cf%3D%5Cfrac%7B345%7D%7B2%2A0.389%7D%5C%5Cf%3D443.4Hz)
Hence the require beat is
.
b. since the length is dependent also on the speed and frequency, we determine the new length when she plays with a fundamental frequency when the speed of sound is 345m/s
using the formula
Now to determine the extension,
![L_{extend}=L_{new}-L_{old}\\L_{extend}=0.39204- 0.38864\\L_{extend}=0.0034m\\](https://tex.z-dn.net/?f=L_%7Bextend%7D%3DL_%7Bnew%7D-L_%7Bold%7D%5C%5CL_%7Bextend%7D%3D0.39204-%200.38864%5C%5CL_%7Bextend%7D%3D0.0034m%5C%5C)
Answer:
vb = 22.13 m/s
So, the only thing that was measured here was the height of point A relative to point B. And the Law of Conservation of Energy was used.
Explanation:
In order to find the speed of roller coaster at Point B, we will use the law of conservation of Energy. In this situation, the law of conservation of energy states that:
K.E at A + P.E at A = K.E at B + P.E at B
(1/2)mvₐ² + mghₐ = (1/2)m(vb)² + mg(hb)
(1/2)vₙ² + ghₐ = (1/2)(vb)² + g(hb)
where,
vₙ = velocity of roller coaster at point a = 0 m/s
hₙ = height of roller coaster at point a = 25 m
g = 9.8 m/s²
vb = velocity of roller coaster at point B = ?
hb = Height of Point B = 0 m (since, point is the reference point)
Therefore,
(1/2)(0 m/s)² + (9.8 m/s²)(25 m) = (1/2)(vb)² + (9.8 m/s²)(0 m)
245 m²/s² * 2 = vb²
vb = √(490 m²/s²)
<u>vb = 22.13 m/s</u>
<u>So, the only thing that was measured here was the height of point A relative to point B. And the Law of Conservation of Energy was used.</u>