ANSWER:
D) centripetal acceleration.
STEP-BY-STEP EXPLANATION:
When a body performs a uniform circular motion, the direction of the velocity vector changes at every instant. This variation is experienced by the linear vector, due to a force called centripetal, directed towards the center of the circumference that gives rise to the centripetal acceleration.
Therefore, the answer is centripetal acceleration.
The centripetal acceleration a is 4.32 
10^-4 m/s^2.
<u>Explanation:</u>
The speed is constant and computing the speed from the distance and time for one full lap.
Given, distance = 400 mm = 0.4 m, Time = 100 s.
Computing the v = 0.4 m / 100 s
v = 4 10^-3 m/s.
radius of the circular end r = 37 mm = 0.037 m.
centripetal acceleration a = v^2 / r
= (4 10^-3)^2 / 0.037
a = 4.32 10^-4 m/s^2.
The Answer Is A
Hope This Helps !
Hey user!
your answer is here..
correct option is A. steel
we know that sounds travel faster in solid as compared to gas and liquids. in gas the molecules are very loosely packed and there is lot of space between so it takes more time to pass sound from each other. and in liquid, the molecules are closer as compared to gas hence it will be little faster and in solid, the molecules are very tightly packed so it will be the fastest. and among these options, steel is the only solid so the speed of sound in steel will be the fastest.
and note that the closer the molecules are to each other ( tightly packed ) makes the bond also tighter and less time to pass sound.
cheers!!
Acceleration = (change in speed) / (time for the change)
-- You said that the airplane has to speed up from zero ("sitting") to 40 m/s, so the change in speed is 40 m/s.
-- You said that it has to roll for 10 seconds to build up enough speed to take off, so the time for the change is 10 s .
Acceleration = (40 m/s) / (10 s)
Acceleration = (40/10) (m/s)/s
<em>Acceleration = 4 m/s²</em>
That seems like no problem. It's only like about 41% of 1 G . That would not even spill the drinks in First Class, or wake up the passengers who are already asleep (like me).
