Brahe & Kepler
Answer from Quizlet
Answer:
Explanation:
Most of this water is locked up in ice, and another 20.9% is found in lakes. Rivers make up 0.49% of surface freshwater. Although rivers account for only a small amount of freshwater, this is where humans get a large portion of their water from.
Hydro electric power is the process of production of electricity from the mechanical energy of water.
In the process of generation of hydro electricity ,large dams are constructed in which the water is stored.The water present at top of the dam has potential energy.The water is driven downward with high pressure. During the falling of water,the potential energy of the water is converted into equivalent kinetic energy. The water coming down with a heavy speed is allowed to fall on a turbine which is connected to a generator.
The mechanical energy of water drives the turbine and electricity is generated due to the electromagnetic induction .
Hence the option A is right i.e falling water that turns the turbine.
Since the device is a speedometer, the data it read is the speed of the racecar. Data recording involving time usually uses time as the independent variable. It was also said in the problem that it records the speed every second which shows that the time interval is constant. This means that only other data, the car's speed, is the dependent variable.
Answer:
frequency is 195.467 Hz
Explanation:
given data
length L = 4.36 m
mass m = 222 g = 0.222 kg
tension T = 60 N
amplitude A = 6.43 mm = 6.43 × 
m
power P = 54 W
to find out
frequency f
solution
first we find here density of string that is
density ( μ )= m/L ................1
μ = 0.222 / 4.36
density μ is 0.050 kg/m
and speed of travelling wave
speed v = √(T/μ) ...............2
speed v = √(60/0.050)
speed v = 34.64 m/s
and we find wavelength by power that is
power = μ×A²×ω²×v / 2 ....................3
here ω is wavelength put value
54 = ( 0.050 ×(6.43 × )²×ω²× 34.64 ) / 2
0.050 ×(6.43 × )²×ω²× 34.64 = 108
ω² = 108 / 7.160 × 
ω = 1228.16 rad/s
so frequency will be
frequency = ω / 2π
frequency = 1228.16 / 2π
frequency is 195.467 Hz
