Answer:
áp dụng công thức í, mình thấy câu này có rắc rối gì đâu
Answer:
c. 2.6 h
Explanation:
The longest time spent over dinner is the time that you have available minus the minimum possible time spent in the trip.
The time of the trip is found using:
t = 
Where distance is d and velocity is v. The time will be minimum at maximum velocity. Replacing with the data we have:
Ttrip =
= 8.1818 h
Tdinner = 10.8h - 8.1818 h = 2.6181h
that aproximates 2.6 h.
Answer:
so rate constant is 4.00 x 10^-4 
Explanation:
Given data
first-order reactions
85% of a sample
changes to propene t = 79.0 min
to find out
rate constant
solution
we know that
first order reaction are
ln [A]/[A]0 = -kt
here [A]0 = 1 and (85%) = 0.85 has change to propene
so that [A] = 1 - 0.85 = 0.15.
that why
[A] / [A]0= 0.15 / 1
[A] / [A]0 = 0.15
here t = (79) × (60s/min) = 4740 s
so
k = - {ln[A]/[A]0} / t
k = -ln 0.15 / 4740
k = 4.00 x 10^-4 
so rate constant is 4.00 x 10^-4 
Scientific knowledge is based upon observation, and it is supplemented by experimentation.<span> Scientific research follows the scientific method, a four-step process that guides scientists in the accumulation of knowledge.</span>
Answer:
a. E = 122.4 N/C
b. E = 58.2 N/C
c. E = 0
Explanation:
The electric field at an arbitrary point away from the axis of the cylinder can found by applying Gauss’ Law, which states that an electric flux through a closed surface is equal to the total charge enclosed by this surface divided by electric permittivity.
In order to apply this law, we have to draw an imaginary cylindrical surface of arbitrary height ‘h’ and radius ‘r’, which is equal to the point where the E-field is asked.
A. For the outside of the cylinder, we will draw our imaginary surface with r = 1.97.

B. This time our imaginary surface should be inside the cylinder, therefore the enclosed charge will be less than that of part A.

C. In this case our imaginary surface will be inside the cylinder, where there is no charge at all. Therefore, the enclosed charge will be zero and the electric field will be zero.