Answer:1.33 hr
Explanation:
Given
Speed of airplane relative to air=627 km/h
Distance traveled =787 km
Speed of wind=38.4 km/h
Wind is blowing in opposite direction therefore net speed is

thus time taken is


I tried dude, but someone got rid of my helpful resource...<span />
Answer:
질문?
Explanation:
평균 공기 밀도가 1.25kg/m³이고 수은 밀도가 13600kg/m³이고 g=10N/kg인 경우 산 기슭의 기압은 수은의 75.0cm이고 정상의 수은은 60cm입니다. 산의 높이를 계산?
Answer:
a) The voltage in an european house is 2,17 times greater than in an american House. That is 183 volts more than in US.
b) the number of cycles or oscillations for an US House is 60 cycles per second
Explanation:
To answer this this question you have to know the wave equation:
x(t) = A Sin (a + b.t)
where
x(t) = is the position as a time function... In this exercise we could call V(t) instead of x(t) beacause we want to know voltage vs time.
A = is the amplitude of the wave. In this case the maximum voltage that can be reached.
a = is the offset in time or number of waves (zero in this exercise)
b = constant that varies the frequency
then...
a) calculate the ratio between both amplitudes:

b) frequency (Oscillations) is:
b = 2pi/T = 2pi*F remember that: T = 1/F
where
F = frequency
T = Period
so for US household we have:
120pi =2pi*F
therefore
F = 120/2 = 60 Hertz