<span>a. A solid will gain kinetic energy and become a liquid.</span>
Answer:at 21.6 min they were separated by 12 km
Explanation:
We can consider the next diagram
B2------15km/h------->Dock
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B1 at 20km/h
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V
So by the time B1 leaves, being B2 traveling at constant 15km/h and getting to the dock one hour later means it was at 15km from the dock, the other boat, B1 is at a distance at a given time, considering constant speed of 20km/h*t going south, where t is in hours, meanwhile from the dock the B2 is at a distance of (15km-15km/h*t), t=0, when it is 8pm.
Then we have a right triangle and the distance from boat B1 to boat B2, can be measured as the square root of (15-15*t)^2 +(20*t)^2. We are looking for a minimum, then we have to find the derivative with respect to t. This is 5*(25*t-9)/(sqrt(25*t^2-18*t+9)), this derivative is zero at t=9/25=0,36 h = 21.6 min, now to be sure it is a minimum we apply the second derivative criteria that states that if the second derivative at the given critical point is positive it means here we have a minimum, and by calculating the second derivative we find it is 720/(25 t^2 - 18 t + 9)^(3/2) that is positive at t=9/25, then we have our answer. And besides replacing the value of t we get the distance is 12 km.
time=distance/speed
1.6/100 secs = 0.016secs=16millisecs
Answer:
C) The function F(x) for 0 < x < 5, the block's initial velocity, and the value of Fr.
Explanation:
Yo want to prove the following equation:
That is, the net force exerted on an object is equal to the change in the kinetic energy of the object.
The previous equation is also equal to:
(1)
m: mass of the block
vf: final velocity
v_o: initial velocity
Ff: friction force
F(x): Force
x: distance
You know the values of vf, m and x.
In order to prove the equation (1) it is necessary that you have C The function F(x) for 0 < x < 5, the block's initial velocity, and the value of F. Thus you can calculate experimentally both sides of the equation.
I think it is electron. Electrons are located outside of the nucleus
