Answer:
f=171.43Hz
Explanation:
Wave frequency is the number of waves that pass a fixed point in a given amount of time.
The frequency formula is: f=v÷λ, where <em>v</em> is the velocity and <em>λ</em> is the wavelength.
Then replacing with the data of the problem,
f=![\frac{120\frac{m}{s} }{0.7m}](https://tex.z-dn.net/?f=%5Cfrac%7B120%5Cfrac%7Bm%7D%7Bs%7D%20%7D%7B0.7m%7D)
f=171.43![\frac{1}{s}](https://tex.z-dn.net/?f=%5Cfrac%7B1%7D%7Bs%7D)
f=171.43 Hz (because
, 1 hertz equals 1 wave passing a fixed point in 1 second).
Answer: a=-2.4525 m/s^2
d=s=190.3 m
Explanation:The only force that is stopping the car and causing deceleration is the frictional force Fr
Fr = 25% of weight
W=mg
W=1750*9.81
W=17167.5
Hence
![Fr=\frac{25}{100} * -17167.5\\\\Fr=-4291.875 N](https://tex.z-dn.net/?f=Fr%3D%5Cfrac%7B25%7D%7B100%7D%20%2A%20-17167.5%5C%5C%5C%5CFr%3D-4291.875%20N)
Frictional force is negative as it acts in opposite direction
According to newton second law of motion
F=ma
hence
![a=Fr/m](https://tex.z-dn.net/?f=a%3DFr%2Fm)
![a=-4291.875/1750\\a=-2.4525](https://tex.z-dn.net/?f=a%3D-4291.875%2F1750%5C%5Ca%3D-2.4525)
given
u= 110 km/h
u=110*1000/3600
u=30.55 m/s
to get t we know that final velocity v=0
![v^2=u^2+2as\\0=30.55^2-2*2.4525*s\\s=190.34m](https://tex.z-dn.net/?f=v%5E2%3Du%5E2%2B2as%5C%5C0%3D30.55%5E2-2%2A2.4525%2As%5C%5Cs%3D190.34m)
Explanation:
The gravitational force equation is the following:
![F_G = G * \frac{m_1 m_2}{r^2} \\](https://tex.z-dn.net/?f=F_G%20%3D%20G%20%2A%20%5Cfrac%7Bm_1%20m_2%7D%7Br%5E2%7D%20%5C%5C)
Where:
G = Gravitational constant = ![6.67408 * 10^{-11} m^3 kg^{-1} s^{-2}](https://tex.z-dn.net/?f=6.67408%20%2A%2010%5E%7B-11%7D%20m%5E3%20kg%5E%7B-1%7D%20s%5E%7B-2%7D)
m1 & m2 = the mass of two related objects
r = distance between the two related objects
The problem gives you everything you need to plug into the formula, except for the gravitational constant. Let me know if you need further clarification.
Answer:
160N
Explanation:
Moments must be conserved - so.
![20 * 0.4 = F * 0.05](https://tex.z-dn.net/?f=20%20%2A%200.4%20%3D%20F%20%2A%200.05)
![F=\frac{20*0.4}{0.05} = 160](https://tex.z-dn.net/?f=F%3D%5Cfrac%7B20%2A0.4%7D%7B0.05%7D%20%3D%20160)