Answer:
(C) The frequency decrease and intensity decrease
Explanation:
The Doppler effect describes the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source, or the wave source is moving relative to the observer, or both.
if the observer and the source move away from each other as is the case for this problem, the wavelength heard by the observer is bigger.
The frequency is the inverse from the wavelength, so the frequency heard will increase.
The sound intensity depends inversely on the area in which the sound propagates. When the buzzer is close, the area is from a small sphere, but as the buzzer moves further away, the wave area will be from a larger sphere and therefore the intensity will decrease.
Answer:
F = 1.68 N
Explanation:
Let's solve this exercise in parts.
Let's use the concept of conservation of the mechanical nerve
initial
Em₀ = 500 J
The energy is totally kinetic
Em₀ = K = ½ m v₀²
v₀ = 
v₀ = √ (2 500/32)
v₀ = 5.59 m / s
now with kinematics we can find a space
v² = v₀² - 2 a x
the negative sign is because the body is stopping
a =
let's calculate
a = (5.59² - 5.1²) / 2 50
a = 0.0524 m / s²
Finally let's use Newton's second law
F = ma
F = 32 0.0524
F = 1.68 N
The dry cleaning process uses chemicals to clean the clothes. It’s “dry” because it doesn't use water, as in normal wet laundering. Most laundries use chemicals to remove grease and stains from clothing.
Speed and velocity are both measured using the same units. The SI unit of distance and displacement is the meter. The SI unit of time is the second. The SI unit of speed and velocity is the ratio of two — the meter per second.
Source: https://physics.info/velocity/
Hope it helps!
Answer:
1.2 Hz
Explanation:
Frequency: This can be defined as the number of cycles completed in one seconds. The unit of frequency is Hertz (Hz)
From the question above,
f = N/t.................... Equation 1
Where f = frequency, N = number of wave or cycle completed by Johnny, t = time take to complete the waves.
Given: N = 12 waves, t = 10 s
Substitute into equation 1
f = 12/10
f = 1.2 Hz
