Answer:
v_f = 0.87 m/s
Explanation:
We are given;
F_avg = -17700 N (negative because it's backward)
m = 117 kg
Δt = 5.50 × 10^(−2) s
v_i = 7.45 m/s
Now, formula for impulse is given by;
I = F•Δt = - 17700 x 5.50 × 10^(−2) = - 973.5 kg.m/s
From impulse momentum theory, we know that;
Change in momentum of particle is equal to impulse.
Thus,
Δp = I = m•v_f - m•v_i
Thus,
-973.5= 117(v_f - 7.45)
Thus,
-973.5/117 = (v_f - 7.45)
-8.3205 + 7.45 = v_f
v_f = - 0.87 m/s
We'll take absolute value as;
v_f = 0.87 m/s
Answer: The correct option is option E (the Sun is seen blocking different constellations in the course of a year.
Explanation:
The earth, which is one of the planets of the solar system that supports life, is shperical in shape. The spherical ( round) shape of the earth is marked by the intervening highlands and oceans on its surface.
Evidence to show that the earth is shperical are:
--> The Lunar eclipse: During an eclipse of the Moon, the shadow of the Earth is always seen to be round.
--> Ships Visibility: When ships travel a large distance away, we see their hulls disappear first and their masts disappear last.
-->Altitude of Polaris (North Star): The height of the North Star changes as we travel to different latitudes. That is ,increases as you move toward the North pole, or decreases as you move toward the equator.
--> Aerial photographs: Photographs of the Earth from space always show a round body.
The statement that doesn't prove that the earth is spherical in shape is (the Sun is seen blocking different constellations in the course of a year). The sun is seen in front of stars blocking different constellation in a year because the earth orbits round the sun in a year and not that it is shperical in shape.
James E. Hansen studied climate change
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:
The wave speed of the sound wave is 900 
.
Explanation:
Wavelength is the minimum distance between two successive points on the wave that are in the same state of vibration. It is expressed in units of length (m).
Frequency is the number of vibrations that occur in a unit of time. Its unit is s⁻¹ or hertz (Hz).
The propagation velocity is the speed with which the wave propagates in the medium, that is, it is the magnitude that measures the speed at which the wave disturbance propagates along its displacement. Relate the wavelength (λ) and the frequency (f) inversely proportional using the following equation: v = f * λ.
In this case:
Replacing:
v= 500 Hz* 1.8 m
v= 900
<u><em>The wave speed of the sound wave is 900 </em></u><u><em>.</em></u>
