Answer:
Friction is useful in some cases like walking and cycling ..
but it is unwanted in machines as it create unwanted sounds and heat .,due to which we loss energy
Explanation:
mark me as brainliest ❤️
Answer:
Explanation:
true because i depends (what market you go to) and how much the vegetable weighs
Answer: Δβ (dB) = -13.1dB
Explanation:
The intensity of sound is inversely proportional to the square of the distance between them.
I ∝ 1/r²
I₁/I₂= r₂²/r₁² .....1
When the listener increases his distance from the source by a factor of 4.49.
Then,
r₂/r₁= 4.49
From equation 1
I₁/I₂ = (4.49)²
I₁/I₂ = 20.16
I₂/I₁ = 1/20.16
The change in sound intensity in dB can be given as
Δβ (dB) = 10 log(I₂/l₁) = 10log(1/20.6) = -13.1dB
Answer:
the smallest angle from the antennas is <em>47.3°</em>
Explanation:
We first need to write the expression for the relation between the wavelength (λ) and the frequency (f) of the wave, and then solve for the wavelength.
Therefore, the relation is:
λ = c /f
where
- c is the speed of light constant
- λ is the wavelength
- f is the frequency
Thus,
λ = (3 × 10⁸ m/s) / (3.4 MHz)
= (3 × 10⁸ m/s) / (3.4 MHz)(10⁶ Hz/1 MHz)
= 88.235 m
Therefore, the smallest angle measured (from the north of east) from the antennas for the constructive interference of the two-radio wave can be calculated as
θ = sin⁻¹(λ / d)
where
- d is the distance between the two radio antennas
Thus,
θ = sin⁻¹(88.235 / 120)
<em>θ = 47.3 °</em>
<em></em>
Therefore, the smallest angle from the antennas, measured north of east, at which constructive interference of two radio waves occurs is <em>47.3 °</em>.
That's 'centripetal acceleration'. It points toward the center of the circle in which the object is traveling, even if it's only a temporary piece of a circle.
