Answer:
it states that energy can neither be created or destroyed
Answer:
3.7 km/h
Explanation:
Let's call v the proper speed of the boat and v' the speed of the water in the river.
When the boat travels in the direction of the current, the speed of the boat is:
v + v'
And it covers 50 km in 3 h, so we can write
(1)
When the boat travels in the opposite direction, the speed of the boat is
v - v'
And it covers 50 km in 5.4 h, so
(2)
So we have a system of two equations: by solving them simultaneously, we find the value of v and v':

Subtracting the second equation from the first one we get:

So, the speed of the water is 3.7 km/h.
Answer: 363 Ω.
Explanation:
In a series AC circuit excited by a sinusoidal voltage source, the magnitude of the impedance is found to be as follows:
Z = √((R^2 )+〖(XL-XC)〗^2) (1)
In order to find the values for the inductive and capacitive reactances, as they depend on the frequency, we need first to find the voltage source frequency.
We are told that it has been set to 5.6 times the resonance frequency.
At resonance, the inductive and capacitive reactances are equal each other in magnitude, so from this relationship, we can find out the resonance frequency fo as follows:
fo = 1/2π√LC = 286 Hz
So, we find f to be as follows:
f = 1,600 Hz
Replacing in the value of XL and Xc in (1), we can find the magnitude of the impedance Z at this frequency, as follows:
Z = 363 Ω
Ans: The thin strands are called as yarns which are made from fibre. Spinning is the process of making yarn. The process where the cotton wool are drawn out and being twisted. This process brings all the fibre together to form a yarn.
Answer:
213 s
Explanation:
Slope is the ratio of change in vertical distance to change in horizontal distance.
Slope = vertical height / horizontal height
Therefore:
6.4% = vertical height / 12.42
vertical height = 6.4% * 12.42
vertical height = 0.8 miles
The distance travelled by the car (s) is:
s² = 0.8² + 12.42²
s² = 154.9
s = 12.45 miles
Acceleration (a) = 2.93 ft/s^2 = 0.00055 mile/s²
initial velocity (u) = 0, final velocity = 203 mph
Using:
s = ut + 0.5at²
12.45 = 0.5(0.00055)t²
t =213 s