A 20000 kg subway train initially traveling at 18.5 m/s slows to a stop in a station and then stays there long enough for its br
1 answer:
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Answer:
11.9 years
Explanation:
We can find the orbital period by using Kepler's third law, which states that the ratio between the square of the orbital period and the cube of the average distance of a planet from the Sun is constant for every planet orbiting aroudn the Sun:
Using the Earth as reference, we can re-write the law as
where
Te = 1 year is the orbital period of the Earth
re = 1 AU is the average distance of the Earth from the Sun
Tj = ? is the orbital period of Jupiter
rj = 5.20 AU is the average distance of Jupiter from the Sun
Substituting the numbers and re-arranging the equation, we find:
Answer:
7.888m
Explanation:
Given:
frequency 'f'= 90Hz
velocity of the sound 'v' = 340 m /sec
The wavelength of the wave is given by,
λ= v/f => 340/90
λ= 3.777m
The destructive interference condition is givn by
Δd= λ
where, m=0,1,2,3,..
m=0, for minimum destructive interference
Δd= x 3.777
Δd=1.888
Therefore, the required distance is
=
+ Δd => 6 + 1.888
= 7.888m
Thus, So the speaker should be placed at 7.888 m