Answer:
y= 240/901 cos 2t+ 8/901 sin 2t
Explanation:
To find mass m=weighs/g
m=8/32=0.25
To find the spring constant
Kx=mg (given that c=6 in and mg=8 lb)
K(0.5)=8 (6 in=0.5 ft)
K=16 lb/ft
We know that equation for spring mass system
my''+Cy'+Ky=F
now by putting the values
0.25 y"+0.25 y'+16 y=4 cos 20 t ----(1) (given that C=0.25 lb.s/ft)
Lets assume that at steady state the equation of y will be
y=A cos 2t+ B sin 2t
To find the constant A and B we have to compare this equation with equation 1.
Now find y' and y" (by differentiate with respect to t)
y'= -2A sin 2t+2B cos 2t
y"=-4A cos 2t-4B sin 2t
Now put the values of y" , y' and y in equation 1
0.25 (-4A cos 2t-4B sin 2t)+0.25(-2A sin 2t+2B cos 2t)+16(A cos 2t+ B sin 2t)=4 cos 20 t
So by comparing the coefficient both sides
30 A+ B=8
A-30 B=0
So we get
A=240/901 and B=8/901
So the steady state response
y= 240/901 cos 2t+ 8/901 sin 2t
Answer:
v = 1/3 m / s = 0.333 m / s
in the direction of the truck
Explanation:
The average speed is defined by the variation of the position between the time spent
v = Δx / Δt
since the position is a vector we must add using vectors, we will assume that the displacement to the right is positive, the total displacement is
Δx = 20 - 15 +20
Δx = 25 m
therefore we calculate
v = 25/75
v = 1/3 m / s = 0.333 m / s
in the direction of the truck
Answer:
Hydrogen has one electron and one proton
Answer: Option (b) is the correct answer.
Explanation:
As Kristina is over training, therefore, there is pain in her muscles because human body also requires rest in order to work or function properly.
That is why, gym trainers suggest to give one day off in a week for your workout sessions so that body muscles should recover.
Thus, we can conclude that if Kristina is over training, then recovery training principle should Kristina consider before continuing her program.
The answers are:
a) 
b) 
Why?
It seems that you forgot to write the questions of the problem, however, in order to help you, I will try to complete it.
The questions are:
a) How much work does the heart do in a day?
b) What is its power output in watts?
So, solving we have:
We need to convert from liter to cubic meters in order to use the given information, so:
Also, we need to find the mass given the density of the blood.
Now, calculating how much work does the heart do in a day, we have:
Then, calculating what is the power output and its horsepower, we have:
Have a nice day!
