When the child is moving, he/she has kinetic energy. For just a brief second before they move the other way, the child is not moving, but they have gravitational potential energy.
The child may need a push from time to time because friction with the air causes loss of energy.
Answer:
Explanation:
given,
diameter of merry - go - round = 2.40 m
moment of inertia = I = 356 kg∙m²
speed of the merry- go-round = 1.80 rad/s
mass of child = 25 kg
initial angular momentum of the system
final angular momentum of the system
from conservation of angular momentum
Answer:
Explanation:
Person A's velocity relative to the train is 0. Therefore, the pitch of the horn will not change.
Given: v0= 18.0 m/s, y0=0m, yf=11m, g=-9.81 m/s^2
v0= initial velocity, vf= final velocity, y0= initial height, yf= final height, g= gravity, sqrt()= square root, ^2=squared
vf^2=v0^2 + (2)(g)(yf-y0)
vf^2=(18.0 m/s)^2+(2)(-9.81 m/s^2)(11 m-0m)
vf^2=18.0 m/s)^2 + (-19.62 m/s^2)(11 m)
vf^2=(324 m^2/s^2) - (215.82 m^2/s^2)
vf^2=108.18 m^2/s^2
vf=sqrt(108.18 m^2/s^2)
vf=10.4 m/s
S = frequency * wavelength
s = 100 * 0.30
s = 30 Hz
hope this helps :)