Answer:
If she stands on the North side of a river flowing to the East at 5 mph,
she must head towards the SouthWest to arrive on the South side of the river directly across from her starting point and we have
x^2 + 5^2 = 10^2 where x is her speed directly across the river
x = (75)^1/2 = 8.66 mph towards the South
sin theta = 5 / 10 = 1/2
She must angle the boat at 30 deg from straight South
Answer:
a) 107.1875 Hz
b) 214.375 Hz
c) 321.5625 Hz
Explanation:
L = length of the open organ pipe = 1.6 m
v = speed of sound = 343 m/s
f = fundamental frequency
fundamental frequency is given as

inserting the values


Hz
b)
first overtone is given as
f' = 2f
f' = 2 (107.1875)
f' = 214.375 Hz
c)
first overtone is given as
f'' = 3f
f'' = 3 (107.1875)
f'' = 321.5625 Hz
Answer:
The Michelson-Morley was designed to detect the motion of the earth through the ether.
No such relation was found and the speed of light is assumed to be the same in all reference frames.
Answer:
B) Gets smaller
Explanation:
The difference of phase between current and voltage in a AC circuit is the phase angle and it depends on the value of Z ( circuit impedance)
Z = R + X where R is the resistive component and X the reactance component, which is due either to a presence of an inductor or a capacitor. In any case the total impedance depends on R the resistive, and the phase angle φ is:
tan⁻¹ φ = X/R
Have a look to a pure capactive circuit (we are talking about AC current) in this case current leads voltage by 90⁰. If we add a resistor in the circuit the current still will lead a voltage but in this condition the phase angle will be smaller,
If R increase, X/R decrease and tan⁻¹ φ also decrease