It is important to maintain septic systems in order to <span>prevent untreated sewage from contaminating groundwater</span>
Answer:
![\frac{0.0125m}{s}](https://tex.z-dn.net/?f=%5Cfrac%7B0.0125m%7D%7Bs%7D)
Explanation:
In order to solve this question we need to know that
. Then we need to convert 4 minutes into seconds and cm into m. We can do that by multiplying the number of minutes by 60 (because there is 60 seconds in one minute) and dividing the number of cm by 100 (because there is 100 cm in one m). So.......
4min = 4 x 60s = 240s
300cm = 300/100 m = 3m
Now we know that distance = 300m, and that the time = 4min = 240s ⇒
⇒ ![speed=\frac{distance}{time} = \frac{3m}{240s} = \frac{0.0125m}{s}](https://tex.z-dn.net/?f=speed%3D%5Cfrac%7Bdistance%7D%7Btime%7D%20%3D%20%5Cfrac%7B3m%7D%7B240s%7D%20%3D%20%5Cfrac%7B0.0125m%7D%7Bs%7D)
Answer:
mu = 0.56
Explanation:
The friction force is calculated by taking into account the deceleration of the car in 25m. This can be calculated by using the following formula:
![v^2=v_0^2+2ax\\](https://tex.z-dn.net/?f=v%5E2%3Dv_0%5E2%2B2ax%5C%5C)
v: final speed = 0m/s (the car stops)
v_o: initial speed in the interval of interest = 60km/h
= 60(1000m)/(3600s) = 16.66m/s
x: distance = 25m
BY doing a the subject of the formula and replace the values of v, v_o and x you obtain:
![a=\frac{v^2-v_o^2}{2x}=\frac{0m^2/s^2-(16.66m/s)^2}{2(25m)}=-5.55\frac{m}{s^2}](https://tex.z-dn.net/?f=a%3D%5Cfrac%7Bv%5E2-v_o%5E2%7D%7B2x%7D%3D%5Cfrac%7B0m%5E2%2Fs%5E2-%2816.66m%2Fs%29%5E2%7D%7B2%2825m%29%7D%3D-5.55%5Cfrac%7Bm%7D%7Bs%5E2%7D)
with this value of a you calculate the friction force that makes this deceleration over the car. By using the Newton second's Law you obtain:
![F_f=ma=(1490kg)(5.55m/s^2)=8271.15N](https://tex.z-dn.net/?f=F_f%3Dma%3D%281490kg%29%285.55m%2Fs%5E2%29%3D8271.15N)
Furthermore, you use the relation between the friction force and the friction coefficient:
![F_f= \mu N=\mu mg\\\\\mu=\frac{F_f}{mg}=\frac{8271.15N}{(1490kg)(9.8m/s^2)}=0.56](https://tex.z-dn.net/?f=F_f%3D%20%5Cmu%20N%3D%5Cmu%20mg%5C%5C%5C%5C%5Cmu%3D%5Cfrac%7BF_f%7D%7Bmg%7D%3D%5Cfrac%7B8271.15N%7D%7B%281490kg%29%289.8m%2Fs%5E2%29%7D%3D0.56)
hence, the friction coefficient is 0.56
The answer to this question would be B (the battery is the electrical power supply)