Answer:
.
Explanation:
When the ball is placed in this pool of water, part of the ball would be beneath the surface of the pool. The volume of the water that this ball displaced is equal to the volume of the ball that is beneath the water surface.
The buoyancy force on this ball would be equal in magnitude to the weight of water that this ball has displaced.
Let 
denote the mass of this ball. Let 
denote the mass of water that this ball has displaced.
Let 
denote the gravitational field strength. The weight of this ball would be 
. Likewise, the weight of water displaced would be 
.
For this ball to stay afloat, the buoyancy force on this ball should be greater than or equal to the weight of this ball. In other words:
.
At the same time, buoyancy is equal in magnitude the the weight of water displaced. Thus:
.
Therefore:
.
.
In other words, the mass of water that this ball displaced should be greater than or equal to the mass of of the ball. Let 
denote the density of water. The volume of water that this ball should displace would be:
.
Given that 
while 
:
.
In other words, for this ball to stay afloat, at least of the volume of this ball should be under water. Therefore, the volume of this ball should be at least 
.
Answer:
When observed from Earth, the wavelengths of light emitted by a star are shifted toward the red end of the electromagnetic spectrum because: the star is moving away from planet Earth.
A star is a giant astronomical or celestial object that contains a luminous sphere of plasma and bounded together by its own gravitational force.
A redshift can be defined as a displacement (shift) of the spectral lines of celestial or astronomical objects toward longer wavelengths (the red end of an electromagnetic spectrum), as a result of the Doppler effect.
Hence, a redshift is considered to be a subtle change in the color of visible electromagnetic radiation from stars (starlight), as observed from planet Earth.
In conclusion, a redshift occur when observing a star from planet Earth because the star is moving away from planet Earth.
Read more: brainly.com/question/17934476
Explanation:
have a great day :)
Answer:
After watching a show about submarines, Jamil wants to learn more about the oceans. The question that could be answered through scientific investigation is What substances dissolve in ocean water?
<u>Explanation:</u>
Jamil's scientific investigation will help him learn about the various substances that can be dissolved in seawater. There is a large number of such substances. Salt is the most important component of seawater.
Sodium chloride is the most common substance. Besides it, magnesium chloride and calcium chloride are also dissolved in seawater. Seawater consists of a large number of gases also such as oxygen, nitrogen, carbon dioxide, etc.
When the object is at rest, there is a zero net force due the cancellation of the object's weight <em>w</em> with the normal force <em>n</em> of the table pushing up on the object, so that by Newton's second law,
∑ <em>F</em> = <em>n</em> - <em>w</em> = 0 → <em>n</em> = <em>w</em> = <em>mg</em> = 112.5 N ≈ 113 N
where <em>m</em> = 12.5 kg and <em>g</em> = 9.80 m/s².
The minimum force <em>F</em> needed to overcome <u>maximum</u> static friction <em>f</em> and get the object moving is
<em>F</em> > <em>f</em> = 0.50 <em>n</em> = 61.25 N ≈ 61.3 N
which means a push of <em>F</em> = 15 N is not enough the get object moving and so it stays at rest in equilibrium. While the push is being done, the net force on the object is still zero, but now the horizontal push and static friction cancel each other.
So:
(a) Your free body diagram should show the object with 4 forces acting on it as described above. You have to draw it to scale, so whatever length you use for the normal force and weight vectors, the length of the push and static friction vectors should be about 61.3/112.5 ≈ 0.545 ≈ 54.5% as long.
(b) Friction has a magnitude of 15 N because it balances the pushing force.
(c) The object is in equilibrium and not moving, so the acceleration is zero.
Answer:
Each part so obtained will represent the fraction 1/8 and the number line obtained will be of the form: To mark 3/8; move three parts on the right-side of zero. To mark 5/8; move five parts on the right-side of zero. To mark -1 3/8 i.e. -11/8; move eleven parts on the left-side of zero.
Explanation:
