What is the unit c denotes here
The relationship between the frequency and wavelength of a wave is given by the equation:
v=λf, where v is the velocity of the wave, λ is the wavelength and f is the frequency.
If we divide the equation by f we get:
λ=v/f
From here we see that the wavelength and frequency are inversely proportional. So as the frequency increases the wavelength decreases.
So the second statement is true: As the frequency of a wave increases, the shorter the wavelength is.
Answer:
98.15 lb
Explanation:
weight of plane (W) = 5,000 lb
velocity (v) = 200 m/h =200 x 88/60 = 293.3 ft/s
wing area (A) = 200 ft^{2}
aspect ratio (AR) = 8.5
Oswald efficiency factor (E) = 0.93
density of air (ρ) = 1.225 kg/m^{3} = 0.002377 slugs/ft^{3}
Drag = 0.5 x ρ x
x A x Cd
we need to get the drag coefficient (Cd) before we can solve for the drag
Drag coefficient (Cd) = induced drag coefficient (Cdi) + drag coefficient at zero lift (Cdo)
where
- induced drag coefficient (Cdi) =
(take note that π is shown as n and ρ is shown as
)
where lift coefficient (Cl)=
=
= 0.245
therefore
induced drag coefficient (Cdi) =
=
= 0.0024
- since the airplane flies at maximum L/D ratio, minimum lift is required and hence induced drag coefficient (Cdi) = drag coefficient at zero lift (Cdo)
- Cd = 0.0024 + 0.0024 = 0.0048
Now that we have the coefficient of drag (Cd) we can substitute it into the formula for drag.
Drag = 0.5 x ρ x
x A x Cd
Drag = 0.5 x 0.002377 x (293.3 x 293.3) x 200 x 0.0048 = 98.15 lb
Answer:
560 kg m/s
Explanation:
First of all, we have to find the velocity of the runner, which is given by the ratio between the distance covered (400 m) and the time taken (50 s):

And now we can calculate the average momentum of the runner, which is equal to the product between the mass of the runner (70 kg) and its velocity, that we have previously calculated:
