24hours is the correct answer
Answer:
Velocity, v = 0.239 m/s
Explanation:
Given that,
The distance between two consecutive nodes of a standing wave is 20.9 cm = 0.209 m
The hand generating the pulses moves up and down through a complete cycle 2.57 times every 4.47 s.
For a standing wave, the distance between two consecutive nodes is equal to half of the wavelength.
Frequency is number of cycles per unit time.
Now we can find the velocity of the wave.
Velocity = frequency × wavelength
v = 0.574 × 0.418
v = 0.239 m/s
So, the velocity of the wave is 0.239 m/s.
Answer:
Visible light
Explanation:
Electromagnetic spectrum is the classification of the electromagnetic waves according to their frequency/wavelength. In order from the shortest to the longest wavelength, we have
Gamma rays
X-rays
Ultraviolet
Visible light
Infrared
Microwaves
Radio waves
All these waves are invisible to human eye, except for the part referred as 'visible light'. The electromagnetic waves of this part of the spectrum are visible to human eye, and they appear as a different color depending on their wavelength. In particular, we have:
Violet: 380-450 nm
Blue: 450-495 nm
Green: 495-570 nm
Yellow: 570-590 nm
Orange: 590-620 nm
Red: 620-750 nm
Answer:
32 amu is the right choice because both protons and neutrons have a mass of 1 amu. Electrons have no mass so go with the last choice
