Answer:48.52 kJ
Explanation:
Given
Resistance
temperature increases from
Voltage=50 V
Heat given(H)
Where V=voltage applied
t=time
R=Resistance
Heat absorbed by water is
where
m=mass of water
c=specific heat of water
=change in temperature
Therefore 90-41.48=48.52 kJ is not absorbed by water and leaves the system into the surroundings.
Answer:
the maximum frequency observed is 2.0044 10⁶ Hz
Explanation:
This is a Doppler effect exercise. Where the emitter is still and the receiver is mobile, therefore the expression that describes the process is
f ’=
the + sign is used when the observer approaches the source
typical speeds of a baby's heart stop are around 200 m / min
let's reduce to SI units
v₀ = 200 m / min (1 min / 60 s) = 3.33 m / s
let's calculate
f ’= 2 10⁶ ()
f ’= 2.0044 10⁶ Hz
f ’= 1,9956 10⁶ Hz
therefore the maximum frequency observed is 2.0044 10⁶ Hz