Answer:
y axis normal (N) and the weight (W)
x axis pplied force (F) and friction force (fr)
Explanation:
If we have a chair on a horizontal surface, the normal (N) and the weight (W) of the body act on the vertical axis.
On the x axis, the applied force (F) acts in the direction of movement and the friction force (fr) in the opposite direction of movement.
In this exercise we assume that the body tends to move to the right, all the forces can be seen in the adjoint
Answer:
student A or B
Explanation:
A common demonstration is to put a ringing alarm clock or bell in the bell jar, and when the vacuum is created, you can no longer hear the sound of the clock/bell.
The bell is connected to a lab pack or batteries and rung to show pupils it can be heard under normal circumstances. The bell jar is then connected to a vacuum pump using a vacuum plate (see Fig 2) and the air is removed from inside creating a near vacuum. The bell is then again rung. This time however, it cannot be heard.
Small low voltage buzzers can be used as a bell replacement for the bell and work in exactly the same way though teachers generally prefer bells as students may be able to see the hammer moving, proving that it is actually ringing even though they cannot hear it.
Some vacuum pumps are better than others at keeping a strong vacuum though if you cannot completely lose the sound, you will at least notice the volume decreasing.
Sound is simply a series of longitudinal waves travelling from the source, through the air to our ears. Without air present, these waves cannot form and therefore sound cannot be conveyed.
In a longitudinal wave the particles oscillate back and forth in the direction of the wave movement unlike transverse waves which like waves on the sea, single particles travel up and down and not in the direction of the wave.
Because you will not be able to create a perfect vacuum, you may still be able to hear the bell ring slightly. Vibrations from the ringing bell can also travel up to the bung in the bell jar which in turn may resonate the jar slightly. This means you may hear the bell ring, however strong the vacuum. To compensate for this, try to insulate the bell as much as possible from the bell jar. Hanging the bell using elastic cord means some of the vibrations will be absorbed by the cord and not be transferred to the bell jar.
Answer:
They can't hear an echo in small room because in it the sound can't be reflected back. For an echo of a sound to be heard,the minimum distance between the source of sound and the walls of the room should be 17.2 m.
hopw it helps
Answer:
>400N is needed to balance that lever
Answer:
Planets are bodies of rock or gas that are named after ancient gods.
Asteroids and Meteoroids are made of rock or metal, which often collide with Earth.
The terrestrial planets are more like the Earth.
The Juno spacecraft is exploring the planet Jupiter.
Explanation:
The planets and other stars in our solar system were similarly baptized. The planets were named after ancient gods. Other stars were baptized with names chosen by scientists or according to their peculiarity. Most of the planets were baptized by ancient Chinese astronomers, and later, by Babylonians. But over time different civilizations changed the names of the planets.
An asteroid is a smaller body in the solar system, usually on the order of just a few hundred kilometers. Meteoroids, in turn, are fragments of rocks that form from comets and asteroids. The luminous effect is produced when fragments of celestial bodies ignite in contact with the Earth's atmosphere due to friction. Both asteroids and meteoroids are made of rock or metal, which often collide with Earth.
The terrestrial planets are the most similar to the earth. These planets are those formed mainly by rocks and metals, have a solid surface without the incidence of rings, as is the case with Mercury, Venus and Mars.
The Juno spacecraft is exploring the planet Jupiter. This probe has already given us several unprecedented discoveries about the largest gas giant in the Solar System, in addition to sending us sensational images showing the complex and beautiful atmosphere of the planet.
