Answer:
my dad is a physics professor so when he comes home i will tell him to answer the question for you
Answer:
I’m pretty positive that it’s 3 seconds
Hope this helps!
Answer:B)439.21 Hz
Explanation:
Given
velocity of train 
frequency of train 
speed of sound 
frequency from Doppler effect can be calculated by





Answer:
the longest time needed to read an arbitrary sector located anywhere on the disk is 2971.24 ms
Explanation:
Given the data in the question;
first we determine the rotational latency
Rotational latency = 60/(3600×2) = 0.008333 s = 8.33 ms
To get the longest time, lets assume the sector will be found at the last track.
hence we will access all the track, meaning that 127 transitions will be done;
so the track changing time = 127 × 15 = 1905 ms
also, we will look for the sectors, for every track rotations that will be done;
128 × 8.33 = 1066.24 ms
∴The Total Time = 1066.24 ms + 1905 ms
Total Time = 2971.24 ms
Therefore, the longest time needed to read an arbitrary sector located anywhere on the disk is 2971.24 ms
This is 6th grade earth science right?