You didn't mention it, but the trumpeter herself has to be standing still.
<span>Person C, the one running towards the trumpeter, hears a pitch
that is higher than B-flat. (A)
Person B, the one running away from the trumpeter, hears a pitch
that is lower than B-flat.
Person D, the one standing still the whole time, hears the B-flat.</span>
Answer:
48.16 %
Explanation:
coefficient of restitution = 0.72
let the incoming speed be = u
let the outgoing speed be = v
kinetic energy = 0.5 x mass x 
- incoming kinetic energy = 0.5 x m x
- coefficient of restitution =

0.72 =
v = 0.72u
therefore the outgoing kinetic energy = 0.5 x m x 
outgoing kinetic energy = 0.5 x m x 
outgoing kinetic energy = 0.5184 (0.5 x m x
)
recall that 0.5 x m x
is our incoming kinetic energy, therefore
outgoing kinetic energy = 0.5184 x (incoming kinetic energy)
from the above we can see that the outgoing kinetic energy is 51.84 % of the incoming kinetic energy.
The energy lost would be 100 - 51.84 = 48.16 %
Answer:
Sound waves are pushed closer together, decreasing wavelength
and increasing frequency.
Answer:
No.
Explanation:
Velocity is a vector quantity which means that it has a certain direction so things that move in different directions DO NOT have the same velocity.
Answer:
F = 176.175 N
Explanation:
given,
radius of merry - go - round = 2.7 m
mass of the disk = 800 kg
speed of the merry- go-round = 18 rpm
= 18 
= 1.88 rad/s
time = 13 s
mass of two children = 25 kg
ω = ω₀ + α t
1.88 = 0 + α(13)
α = 0.145 rad/s²
we know
τ = I α
so,
τ = I α
τ = 3280.5 x 0.145
τ = 475.67 N m
τ = F x r
475.67 = F x 2.7
F = 176.175 N