I think the answer is Ten. Hope i helped
just asking do you do K-12
Answer:![\dfrac{1}{20}](https://tex.z-dn.net/?f=%5Cdfrac%7B1%7D%7B20%7D)
,20
,15.7![ms^{-1}](https://tex.z-dn.net/?f=ms%5E%7B-1%7D)
Explanation:
Frequency is defined as the number of revolutions made the object in unit time.
Given that it takes
minutes
revolutions.
So,
revolutions can be completed in
minute.
So,
revolutions can be completed in a second.
So,frequency is ![\frac{1}{20}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B20%7D)
Period of a object is the inverse of frequency.
Inverse of frequency ![\frac{1}{\frac{1}{20} }=20](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7B%5Cfrac%7B1%7D%7B20%7D%20%7D%3D20)
So,period is
.
Speed of car is the given by the ratio of distance covered in one revolution to the time period.
Distance travelled in one period is
where
is the diameter.
Given that ![d=100m](https://tex.z-dn.net/?f=d%3D100m)
So,distance travelled in one revolution ![\pi \times 100=315.15m](https://tex.z-dn.net/?f=%5Cpi%20%5Ctimes%20100%3D315.15m)
Time period is
.
Speed is ![\frac{314.15}{20}=15.7ms^{-1}](https://tex.z-dn.net/?f=%5Cfrac%7B314.15%7D%7B20%7D%3D15.7ms%5E%7B-1%7D)
Answer:
4.11 m/s
Explanation:
Given:
v₀ₓ = 1.25 m/s
aₓ = 0 m/s²
v₀ᵧ = 0 m/s
aᵧ = -9.8 m/s²
t = 0.4 s
Find: v
First, in the x direction:
vₓ = aₓt + v₀ₓ
vₓ = (0 m/s²) (0.4 s) + 1.25 m/s
vₓ = 1.25 m/s
And in the y direction:
vᵧ = aᵧt + v₀ᵧ
vᵧ = (-9.8 m/s²) (0.4 s) + 0 m/s
vᵧ = -3.92 m/s
The net speed is found with Pythagorean theorem:
v² = vₓ² + vᵧ²
v² = (1.25 m/s)² + (-3.92 m/s)²
v = 4.11 m/s
Answer:
123.18 nm
Explanation:
Given:
- Refractive index of the glass=1.5
- Index of magnesium fluoride=1.38
- Wavelength of the light =680 nm
Let t be the thickness of the film. The relation between the wavelength of light in film and thickness of the film in order to have no reflection is given by
![2t=\dfrac{\lambda_{film}}{2}\\t=\dfrac{\lambda_{film}}{4}](https://tex.z-dn.net/?f=2t%3D%5Cdfrac%7B%5Clambda_%7Bfilm%7D%7D%7B2%7D%5C%5Ct%3D%5Cdfrac%7B%5Clambda_%7Bfilm%7D%7D%7B4%7D)
Now According to question we have
![\lambda_{film}=\dfrac{\lambda_{film}}{n}](https://tex.z-dn.net/?f=%5Clambda_%7Bfilm%7D%3D%5Cdfrac%7B%5Clambda_%7Bfilm%7D%7D%7Bn%7D)
where n is the refractive index of the film.
![\lambda_{film}=\dfrac{680}{1.38}\\\lambda_{film}=492.75\ nm](https://tex.z-dn.net/?f=%5Clambda_%7Bfilm%7D%3D%5Cdfrac%7B680%7D%7B1.38%7D%5C%5C%5Clambda_%7Bfilm%7D%3D492.75%5C%20nm)
Now thickness t is given by
![t=\dfrac{492.75}{4}\\t=123.18\ \rm nm](https://tex.z-dn.net/?f=t%3D%5Cdfrac%7B492.75%7D%7B4%7D%5C%5Ct%3D123.18%5C%20%5Crm%20nm)
Hence the thickness of the film is calculated in order to have no reflection.
Answer:
All matter contained electrons
Explanation:
The discovery and characterization of cathode ray suggested that it was a subatomic particle and cathode ray ( electron) was the first discovered. It immensely became the strong explanatory tool for chemical bond. This can be attributed to the the ease with which electron move from one atom to the other.