A scientist can assess whether a pure niobium sample is responsible for contaminating the lab with radioactivity by testing the sample. By testing the niobium sample, a scientist can determine whether it has any other element.
Answer:
37.545 m/s
Explanation:
f' = Actual frequency of horn = 269 Hz
f = Observed frequency of horn = 290 Hz
v = Speed of sound in air = 343 m/s
= Speed of second train = 13.7 m/s
= Speed of first train
From Doppler effect we have

The speed of the first train is 37.545 m/s
Recall that average velocity is equal to change in position over a given time interval,

so that the <em>x</em>-component of
is

and its <em>y</em>-component is

Solve for
and
, which are the <em>x</em>- and <em>y</em>-components of the copter's position vector after <em>t</em> = 1.60 s.


Note that I'm reading the given details as

so if any of these are incorrect, you should make the appropriate adjustments to the work above.
Answer:

Explanation:
We are given that







We have to find the exit temperature.
By steady energy flow equation



Substitute the values



