If Kevin is good, really good, he can use the principle of the
Doppler effect to distinguish the sound of an approaching train
from the sound of a departing train.
-- The sound of a train APPROACHING the station will have a HIGHER
pitch than the sound actually emitted by the train.
-- The sound of a train moving AWAY from the station will have a LOWER
pitch than the sound actually emitted by the train.
But the skill that Kevin will need is to exactly know the sound actually
emitted by the train ... without hearing it ... and to be able to compare
that to the sound that he DOES hear at the moment. Not easy.
Answer:
C)
Explanation
maybe a but its most likely c
its def. not 4 and def. not 2
Answer:
West
Explanation:
This is because the first caar has more mass
DE = DC + CE
27 = 3v - 30 + 6v - 15
27 = 9v - 45
v = 8
The Toroid is form when you have wound conductor around circular body. In this case you have magnatic field inside the core but you dont have any poles because circular body dont have ends. This can be used where you want minimum flux leakage and dont need magnatic poles. i.e. toroidal inductor, toroidal transformer.
The Solenoid is forn when you wound conductor around body with limb. In this case magnatic field creates two poles N and S. Solenoids have little bit flux leakage. This used where you want magnatic poles and flux leakage is not an issue. i.e. relay, motors, electromagnates.
1 == toroid
2= solenoid