200 million drivers in the untied states
Answer:
The reflectivity at the boundary of the two grains is 
×
Step-by-step explanation:
Given :
Refractive index of one grains (
) = 1.553
Refractive index of second grains (
) = 1.544
According to the fresnel equation,
∴ general equation of refraction ( reflectivity ) 
where 
= incident angle, 
= transmitted angle
but for normal incidence 
°
so our equation become,
⇒ 
×
Therefor reflectivity at the boundary is given by ×.
Answer:
dh/dt=9.82x10^-3 ft/min
Step-by-step explanation:
1. You have that the rate is10 ft³/min. Then:
dV/dt=10
2. The formula for calculate the volume of a cone, is:
V=1/3(πr²h)
"r" is the radius and "h" is the height.
3. The diameter of the base of the cone is approximately 3 times the altitude. Then, the radius is:
r=diameter/2
diameter=3h
r=3h/2
4. When you susbstitute r=3h/2 into the formula V=πr²h/3, you have:
V=1/3(πr²h)
V=1/3(π(3h/2)²(h)
V=1/3(π9h²/4)(h)
V=9πh³/12
5. Therefore:
dV/dt=(9πh²/4)dh/dt
h=12
dV/dt=10
6. When you substitute the values of dV/dt and h into dV/dt=(9π(12)²/4)dh/dt, you have:
dV/dt=(9π(12)²/4)dh/dt
10=(1017.876)
7. Finally, you obtain:
dh/dt=10/1017.876
dh/dt=9.82x10^-3 ft/min
