Answer:
- the expected value is 8
- the standard deviation is 2.8284
Explanation:
Given the data in the question;
The model N(t), the number of planets found up to time t, as a poisson process,
∴ N(t) has distribution of poisson distribution with parameter (λt)
so
the mean is;
λ = 1 every month = 1/3 per month
E[N(t)] = λt
E[N(t)] = (1/3)(24)
E[N(t)] = 8
Therefore, the expected value is 8
For poisson process, Variance and mean are the same,
Var[N(t)] = Var[N(24)]
Var[N(t)] = E[N(24)]
Var[N(t)] = 8
so the standard deviation will be;
σ[N(24)] = √(Var[N(t)] )
σ[N(24)] = √(8 )
σ[N(24)] = 2.8284
Therefore, the standard deviation is 2.8284
Answer: 405.3 minutes
Explanation: In order to explain this problem we have to use the following:
Fisrtly we calculate the volume of the wire, this is given by:
Vwire=π*r^2*L where r and L are the radius and L the length of teh wire, respectively.
Vwire=π*1.25*10^-3*0.26=1.27*10^-6 m^3
then the number of the total electrons in tthe wire volume is given by;
n° electrons in the wire=ρ*Vwire=8.4*10^28*1.27*10^-6 m^3=1.07 *10^23
Finally, considering the current in the wire equal to 4.4*10^18 electrons/s
the time consuming to extract all the electrons from the wire is given by:
t= total electrons in the wire/ current=1.067*10^23/4.4*10^18=24,318 s
equivalent to 405.3 minutes
Answer:
The potential energy of the hiker is
.
Explanation:
Given that,
Mass of the hiker, m = 61 kg
Height above sea level, h = 1900 m
We need to find the potential energy associated with a 61-kg hiker atop New Hampshire's Mount Washington. The potential energy is given by :

g is the acceleration due to gravity

So, the potential energy of the hiker is
. Hence, this is the required solution.
Number 2- Liquids
Number 3- Cells