Answer:
c. Resin.
Explanation:
Amber is a resin.
Which of the following can be used to measure temperature accurately
Celsius
Fahrenheit
Kelvin
All of these are correct
Answer:
Any of those terms can be converted to either of the other terms, so either term is correct. People are accustomed to everyday temperatures in Fahrenheit. The ideal gas law specifies that
P V = N R T where T is in Kelvin which is Celsius + 273 deg.
Henri becquerel shared a nobel prize for his work in discovering what?.
80 POINTS MARK BRAINLIEST this experiment is to see if water flows faster oit of a smaller can or a larger can. you will need: two cans (one quite small like a soup can and the other large, like a juice can.) follow these steps: remove the top of each can punch a hole in the side of each can, very close to the bottem, making sute the holes are equal in size. Cover each hole with a peice of tape, and place the cans next to the sink. b. put tje water in both cans, making sure the water is at the same level - different ampuns, but the same level. turn the cans so the holes are facing into the sink, and remove the tape at the time. answer these questions: do the streams of water shoot out at the same distance? why or why not? c. try the same experiment, but this time put one cup of water in each can. whst happens to the streams of water now? d. try the same experiment, but the time put one cup of water in each can. whst happens to the streams of water now? d. try the same experiment but this time fill the cans to thw top. what happens to the streams of water? ANSWER ALL PARTS
The water present in the middle doesn't experience pressure as much as that experienced by water at the bottom. Pressure is more at bottom surface hence fluids flow from higher pressure to lower pressure. This is why the water rushes out from the bottom hole much faster than from the upper hole
Collette is twisting a screwdriver. The scredriver has a handle with a radius of 18 mm. If she is exerting a force of 14 N, how much torque is she causing? PLEASE HELPPP!!!!
A. 25 Nm
B. 0.25 Nm
C. 1.3 Nm
D 0.75 Nm
Torque:-
[tex]\\ \rm\Rrightarrow \tau =14(0.018)[/tex]
[tex]\\ \rm\Rrightarrow \tau=0.25Nm[/tex]
option B
Two horses pull horizontally on ropes attached to a tree stump each horse pulls with a force of F if the angle between the two ropes is 126° what's resultant force?
Answer:
126 / 2 = 63 = angle between one rope and the direction of the resultant force
t = F cos 73 = .45 F force on stump due to one horse
T = 2 t = .90 F force on stump due to both horses - T would be the resultant of the two horses each pulling with force F
Which characteristic is common to the four outer planets in our solar system?.
Answer: They Are all gas giants.
Explanation:
1 point
8. A magnetic field of 30 T is directed perpendicular to the force of a coil
with an area of 0.36 m^2. Calculate the magnetic flux in the coil.
A)0.27 Wb
B)9.3 Wb
C)10.8 Wb
D)83.3 Wb
Answer:
the answer is. C.
Explanation:
[tex] 0.36 \times 30 = 10.8[/tex]
the solution
The voltage across the secondary winding is 10,000 v, and the voltage across the primary winding is 25,000 v. if the primary winding has 200 coils, how many coils are in the secondary winding? 50 coils 80 coils 125 coils 500 coils
Answer: 80 coils
Explanation for 80 coils: voltage across the secondary winding is 10,000 V, and the voltage across the primary winding is 25,000 V. If the primary winding has 200 coils, how many coils are in the secondary winding...The voltage across the primary winding is 6000 V!
Complete the mechanism for the given reaction by adding the missing bonds, charges, nonbonding electrons, and curved arrows
The mechanism for the given reaction by adding the missing bonds, charges, nonbonding electrons, and curved arrows is as represented in the attached image.
Mechanism of Organic ReactionsThe representation of an organic reaction mechanism typically includes designation of the overall reaction type (which may be substitution, addition, elimination, oxidation, reduction, or rearrangement), the presence of any reactive intermediates, the nature of the reagent that initiates the reaction, the presence of any catalysis as facilitated by a catalyst, and ultimately it's stereochemistry.
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The mechanism for the given reaction is depicted in the attached picture by adding missing bonds, charges, nonbonding electrons, and curved arrows.
What is organic reaction mechanisms?The existence of any reactive intermediates, the nature of the reagent that begins the reaction, the presence of any catalysis as helped by a catalyst.
Finally the stereochemistry of an organic reaction mechanism are all included in the depiction of an organic reaction mechanism.
Hence the mechanism for the given reaction is depicted in the attached picture by adding missing bonds, charges, nonbonding electrons, and curved arrows.
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A soft foam block of mass m slides without friction in the
positive x-direction with speed v. At time t = 0, a student briefly
pushes the block with a force probe in the positive x-direction. The
graph to the right shows the force probe's measurements as a
function of time during the push. Which of the following statements
is true about the block's momentum between t = 0 and t = t;?
The true statement about the blocks momentum is : The momentum of the block has increased by approximately 1/2 F₀t₁ ( B )
Change in MomentumGiven that the change in momentum is equivalent to the Area which is under the force time graph
where :
Area under the force time graph = 1/2 F₀t₁ . Therefore we can conclude that the momentum of the block has increased by an equivalent value of the are under the time graph.
Hence we can conclude that the true statement about the blocks momentum is The momentum of the block has increased by approximately 1/2 F₀t₁ .
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Attached below is the missing part of your question
missing options
The momentum of the block has decreased to zero at time t1. - AThe momentum of the block has increased by approximately 1/2 F0t1 - BThe momentum of the block has decreased by approximately 1/2 F0t1 - CThe change in momentum cannot be determined without knowing the distance by which the force probe compressed the block. - D7. An object with a mass of 2.0 kg is accelerated from rest. The above graph shows the magnitude of the net force
as a function of time. At t = 4.0 s the object's velocity is closest to which of the following?
a. 2.0 m/s
b. 4.0 m/s
C. 10 m/s
d. 13 m/s
The object's velocity accelerating from rest from the applied force and time is closest to 4 m/s.
Velocity of the object
The velocity of the object can be determied by applying Newton's second law of motion as shown below;
F = ma
where;
F is the applied forcem is the mass of the objecta is the acceleration of the objectThe acceleration of the object is calculated as follows;
a = F/m
at time, t 4.0 s, the corresponding force = 2 N
a = 2/2
a = 1 m/s²
Velocity of the object is calculated as;
v = u + at
v = 0 + 1 x 4
v = 4 m/s
Thus, the object's velocity accelerating from rest from the applied force and time is closest to 4 m/s.
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Which is the destructive interference formula for diffraction grating problems? dsin = dcos = dcos = n dsin = n.
The destructive interference formula for diffraction grating problems is [tex]d sin \theta = (n+\frac{1}{2})\lambda[/tex].
What is the definition of destructive interference?Destructive interference happens when the maxima of two waves are 180° out of phase a positive displacement of one wave is canceled exactly by a negative displacement of the other wave.
The formula for brighter patches resulting from constructive interference and darker patches resulting from destructive interference in a diffraction grating is:
[tex]\rm d sin \theta = n \lambda[/tex]
The grating spacing is denoted by d, the angle of light is denoted by a the fringe order is denoted by n, and the wavelength is denoted by [tex]\rm \lambda[/tex].
The destructive interference formula is now based on the fact that destructive interference occurs between the fringes.
Hence the destructive interference formula for diffraction grating problems is [tex]d sin \theta = (n+\frac{1}{2})\lambda[/tex].
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Answer:
A. dsin =
Explanation:
What is the length of a pendulum that has a period of 4. 89 seconds?
Hi there!
We can use the following equation for a simple pendulum:
[tex]T = 2\pi \sqrt{\frac{L}{g}}[/tex]
T = Period (4.89 s)
L = length (? m)
g = acceleration due to gravity (9.8 m/s²)
Rearrange the equation to solve for L.
[tex]T^2 = 4\pi ^2 \frac{L}{g}\\\\L = \frac{gT^2}{4\pi ^2}[/tex]
[tex]L = \frac{(9.8)(4.89^2)}{4\pi^2} = \boxed{5.936 \frac{m}{s}}[/tex]
A pendulum is a body hanging from a fixed point that swings back and forth under the effect of gravity. The length of a pendulum that has a period of 4.89 seconds is 5.936 meters.
What is a pendulum?A pendulum is a body hanging from a fixed point that swings back and forth under the effect of gravity. Pendulums are employed to govern the movement of clocks because the time interval for each full oscillation, known as the period, remains constant.
Given that the time period is 4.89 seconds, therefore, the length of the pendulum can be written as,
[tex]\rm T = 2\pi \sqrt{\dfrac{L}{g}}\\\\4.89 = 2\pi \sqrt{\dfrac{L}{9.81}}\\\\L = 5.936\ m[/tex]
Hence, the length of a pendulum that has a period of 4.89 seconds is 5.936 meters.
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The free-body diagram below represents all the forces acting on an object. What is the net force acting on this object?
300 N right
100 N down
0 N up
200 N right
Answer:
200 N to the right
Explanation:
The 50 N forces cancel each other since they are opposing each other.A light-year is a unit of measurement that would most appropriately be used to measure which distance?
a. Between two galaxies b. Between Earth and Jupiter c. Between Earth and the sun d. Between the moon and Earth
A light-year is a unit of measurement which is used to measure distance between the Earth and the sun.
What is Light year?This is defined as the distance light travels in the time it takes the Earth to orbit the Sun.
It is also the distance a beam of light travels in a single earth year which is why option C was chosen as the most appropriate choice.
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What are the postulates of the KMT of gases?
Arm ab has a constant angular velocity of 16 rad/s counterclockwise. At the instant when theta = 60
The linear acceleration of collar D when θ = 60° is - 693.867 inches per square second.
How to determine the angular velocity of a collarIn this question we have a system formed by three elements, the element AB experiments a pure rotation at constant velocity, the element BD has a general plane motion, which is a combination of rotation and traslation, and the ruff experiments a pure translation.
To determine the linear acceleration of the collar ([tex]a_{D}[/tex]), in inches per square second, we need to determine first all linear and angular velocities ([tex]v_{D}[/tex], [tex]\omega_{BD}[/tex]), in inches per second and radians per second, respectively, and later all linear and angular accelerations ([tex]a_{D}[/tex], [tex]\alpha_{BD}[/tex]), the latter in radians per square second.
By definitions of relative velocity and relative acceleration we build the following two systems of linear equations:
Velocities[tex]v_{D} + \omega_{BD}\cdot r_{BD}\cdot \sin \gamma = -\omega_{AB}\cdot r_{AB}\cdot \sin \theta[/tex] (1)
[tex]\omega_{BD}\cdot r_{BD}\cdot \cos \gamma = -\omega_{AB}\cdot r_{AB}\cdot \cos \theta[/tex] (2)
Accelerations[tex]a_{D}+\alpha_{BD}\cdot \sin \gamma = -\omega_{AB}^{2}\cdot r_{AB}\cdot \cos \theta -\alpha_{AB}\cdot r_{AB}\cdot \sin \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \cos \gamma[/tex] (3)
[tex]-\alpha_{BD}\cdot r_{BD}\cdot \cos \gamma = - \omega_{AB}^{2}\cdot r_{AB}\cdot \sin \theta + \alpha_{AB}\cdot r_{AB}\cdot \cos \theta - \omega_{BD}^{2}\cdot r_{BD}\cdot \sin \gamma[/tex] (4)
If we know that [tex]\theta = 60^{\circ}[/tex], [tex]\gamma = 19.889^{\circ}[/tex], [tex]r_{BD} = 10\,in[/tex], [tex]\omega_{AB} = 16\,\frac{rad}{s}[/tex], [tex]r_{AB} = 3\,in[/tex] and [tex]\alpha_{AB} = 0\,\frac{rad}{s^{2}}[/tex], then the solution of the systems of linear equations are, respectively:
Velocities[tex]v_{D}+3.402\cdot \omega_{BD} = -41.569[/tex] (1)
[tex]9.404\cdot \omega_{BD} = -24[/tex] (2)
[tex]v_{D} = -32.887\,\frac{in}{s}[/tex], [tex]\omega_{BD} = -2.552\,\frac{rad}{s}[/tex]
Accelerations[tex]a_{D}+3.402\cdot \alpha_{BD} = -445.242[/tex] (3)
[tex]-9.404\cdot \alpha_{BD} = -687.264[/tex] (4)
[tex]a_{D} = -693.867\,\frac{in}{s^{2}}[/tex], [tex]\alpha_{BD} = 73.082\,\frac{rad}{s^{2}}[/tex]
The linear acceleration of collar D when θ = 60° is - 693.867 inches per square second. [tex]\blacksquare[/tex]
RemarkThe statement is incomplete and figure is missing, complete form is introduced below:
Arm AB has a constant angular velocity of 16 radians per second counterclockwise. At the instant when θ = 60°, determine the acceleration of collar D.
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How much force does the astronaut exert on his chair while accelerating straight up at 10.0 m/s2m/s2
Answer:
M a = Fc -M g
Use up as positive - a is the acceleration upwards
Fc = M (a + g) force exerted by chair
Fc = 19.8 M m/s^2 where M is the mass of the astronaut
The force exerted by the astronaut accelerating straight up with an acceleration of 10 m/s² is m/5 Newton.
What is force?If you want to accelerate a body of mass 'm' with acceleration 'a' than a force of magnitude given by the product of mass and acceleration is needed.
Given is an astronaut accelerating straight up with an acceleration of 10 m/s².
Since the astronaut is moving in upward direction, the resultant resultant force is in upward direction. Now, assume that the force exerted by the astronaut on the chair is F[A]. The normal reaction force on the astronaut will also be same. Mathematically -
F[N] = F[A]
Now, we can write the resultant normal reaction force as -
ma - mg = F[N]
F[N] = m(a - g)
F[N] = m(10 - 9.8)
F[N] = m(0.2)
F[N] = m/5
F[A] = F[N] = m/5
where m is the mass of astronaut.
Therefore, the force exerted by the astronaut accelerating straight up with an acceleration of 10 m/s² is m/5 Newton.
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Which characteristic is the same for every color of light in a vacuum?.
In a vacuum all colors of light travel with same speed and this is the reason a white ray travels through the vacuum without going through any dispersion..
What is speed?Speed of light is the distance per time light waves propagate through different materials. The value for the speed of light in a vacuum is now defined as exactly 299,792,458 metres per second.
Therefore, In a vacuum all colors of light travel with same speed and this is the reason a white ray travels through the vacuum without going through any dispersion
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A 50,0 g silver spoon at 20.0°C is placed in a cup of coffee at
90.0°C. How much heat does the spoon absorb from the coffee to
reach a temperature of 89.0°C?
The heat capacity of the silver spoon at the given temperature difference is 817.65 J.
Heat capacity of the silver spoon
The heat capacity of theb silver spoon is the quantity of heat absorbed by the silver spoon. The heat capacity of the silver spoon at the given temperature difference is calculated as follows;
Q = mcΔθ
where;
m is mass of the spoonc is specific heat capacity of silver = 0.237 J/g⁰CΔθ is change in temperatureQ = 50 x 0.237 x (89 - 20)
Q = 817.65 J
Thus, the heat capacity of the silver spoon at the given temperature difference is 817.65 J.
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Hello people ~
Sound cannot travel through
(a) air
(b) water
(c) air
(d) vacuum
Answer:
Vaccum
Explanation:
Sound travels through the particles of different matter In vaccum there is no air so no matter and so no particles .So sound can't travel through vaccum.You can test it .
Take a speaker and keep it inside a bottle ,close it .You won't hear any soundWhich statement explains how the charges on objects determine the electric force between them? (1 point)
O Objects with positive charges repel each other, and objects with negative charges attract each other
O Objects with the same charge attract each other, and objects with opposite charges repel each other
O Objects with positive charges attract each other, and objects with negative charges repel each other.
O Objects with the same charge repel each other, and objects with opposite charges attract each other
Objects with the same charge repel each other, and objects with opposite charges attract each other
Effect of similar charges on each otherAccording to Coulomb, the electric force for charges at rest has the following properties: Like charges repel each other; unlike charges attract. Thus, two negative charges repel one another, while a positive charge attracts a negative charge. The attraction or repulsion acts along the line between the two charges.
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30. (a) What is the effect on the period of a pendulum if you double its length?
(b) What is the effect on the period of a pendulum if you decrease its length by 5.00%?
The answers are "(a) Period increases by a factor of 1.41 (2–√)(b) Period decreases to 97.5% of old period" but please include all of your work.
Let's know the formula
[tex]\\ \rm\rightarrowtail T=2\pi \sqrt{\dfrac{l}{g}}[/tex]
So
[tex]\\ \rm\rightarrowtail T\propto \sqrt{l}[/tex]
Hence if length is doubled time period will be √2 times
√2=1.41 (Approximately)#2
Decrease by 5% will decrease the time period 5/2=2.5%
So
It's
100-2.5=97.5% of old periodWhat is the speed of a wave that has a frequency of 440 Hz and a wavelength of 0.78 m? O A. 564 m/s m B. 0.003 m/s C. 343 m/s D. 0.002 m/s
Explanation:
velocity = frequency × wave length
velocity = 440 × 0.78
velocity = 343 m/sec
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When we harness energy using photovoltic cells in a large panel on the roofs of buildings, we are using
power
A solar
B geothermal
C wind
D biomass
Answer:
solar
Explanation:
this is a form of solar panel
A solid sphere is released from the top of a ramp that is at a height
h1 = 2.20 m.
It rolls down the ramp without slipping. The bottom of the ramp is at a height of
h2 = 1.87 m
above the floor. The edge of the ramp is a short horizontal section from which the ball leaves to land on the floor. The diameter of the ball is 0.14 m.
a.) Through what horizontal distance d, in meters, does the ball travel before landing?
b.) How many revolutions does the ball make during its fall?
Hi there!
We can use the work-energy theorem and apply it to this situation.
At the top of the ramp, the ball only has gravitational potential energy, and at the bottom of the ramp, the ball has BOTH translational and rotational kinetic energy.
We must use the following equations:
[tex]GPE = mgh \\KE_T = \frac{1}{2}mv^2\\\\KE_R = \frac{1}{2}I \omega^2[/tex]
m = mass of sphere (kg)
g = acceleration due to gravity (m/s²)
h = height of ramp (m)
v = final velocity (m/s)
I = Moment of Inertia (kgm²)
ω = angular velocity (rad/sec)
Since:
[tex]E_i = E_f\\\\mgh = \frac{1}{2}mv^2 + \frac{1}{2}I\omega ^2[/tex]
In order to make things easier, since the ball is not slipping, we can relate angular velocity to translational velocity:
[tex]\omega = \frac{v}{r}[/tex]
Also, recall the equation for the moment of inertia for a solid sphere:
[tex]I = \frac{2}{5}mr^2[/tex]
We can use these to simply our equation:
[tex]KE_R = \frac{1}{2}(\frac{2}{5}mr^2)(\frac{v}{r})^2 = \frac{1}{5}mv^2[/tex]
Now, we can rewrite the equation and solve for 'v'.
[tex]mgh = \frac{1}{2}mv^2 + \frac{1}{5}mv^2\\\\mgh = \frac{7}{10}mv^2\\\\v = \sqrt{\frac{10gh}{7}} = \sqrt{\frac{10(9.8)(2.2 - 1.87)}{7}} = 2.149\frac{m}{s}[/tex]
a)
We can begin by solving for the time taken for the ball to land on the ground. The ball only has a horizontal velocity, so this is essentially a free-fall situation. Use the rearranged kinematic equation:
[tex]t = \sqrt{\frac{2h}{g}} = \sqrt{\frac{2(1.87)}{9.8}} = .6178 s[/tex]
Now, use the following equation to solve for horizontal distance given horizontal velocity and time:
[tex]d_x = v_x t\\\\d_x = 2.149 * .6178 = \boxed{1.328 m}[/tex]
b)
We can use the previously-stated relationship between translational and angular velocity to solve for the angular velocity.
[tex]\omega = \frac{v}{r}[/tex]
It is given that the diameter is 0.14 m, so the radius is 1/2th the diameter, or 0.07 m.
Solve for the angular velocity:
[tex]\omega = \frac{2.149}{0.07} = 30.706 \frac{rad}{sec}}[/tex]
Using the above fall time and dimensional analysis to convert from rad/sec to revolutions, we can solve for the # of revolutions made by the ball:
[tex]\frac{30.706rad}{sec} * .6178 sec * \frac{1 rev}{2\pi rad} = \boxed{3.019 rev}[/tex]
What does the area of an acceleration time graph represent?
The area under the acceleration time graph represents change in velocity
The graph is plotted with acceleration on the vertical axis and time on the horizontal axis. The area under such graph represents change in velocity
The area of an acceleration- time graph represents the change in velocity. The pace at which a body's velocity varies is represented by acceleration, which is a vector quantity.
What is acceleration?The rate of change of velocity with respect to time is known as acceleration. According to Newton's second law, the eventual effect of all forces applied to a body is its acceleration.
The formula for acceleration is;
[tex]\rm a = \frac{v-u}{t}[/tex]
u is the initial speed
v is the final speed
t is the time interval
a is the acceleration of a ball
Hence the area of an acceleration- time graph represents the change in velocity.
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Given the velocity v= ds dt and the initial position of a body moving along a coordinate line, find the body's position at time t
For the body's position at time t is mathematically given as
s(t)=4.9t^2+5t+16
What is the body's position at time t
Generally, the equation for the velocity is mathematically given as
v=ds/dt
v=9.8t+5 as velocity
s=4.9t^2+5t+c
s(0)=16
16=c
s(t)=4.9t^2+5t+16
In conclusion the body's position at time t
s(t)=4.9t^2+5t+16
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The body position at the given time t is s = 4.9t² + 5t + 16 if the velocity v= ds/dt and the initial position of a body moving along a coordinate line.
What is the distance?A numerical representation of the distance between two items or locations is called distance. A physical length or an approximation based on other considerations in physics or common usage can be referred to as distance.
We have:
[tex]\rm v = \frac{ds}{dt}[/tex]
[tex]\rm v = 9.8t+5[/tex] is the velocity
[tex]\rm s = 4.9t^2+5t+c[/tex] is the speed
At t = 0 s(0) = 16
16 = c
[tex]\rm s = 4.9t^2+5t+16[/tex]
Thus, the body position at the given time t is s = 4.9t² + 5t + 16 if the velocity v= ds/dt and the initial position of a body moving along a coordinate line.
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Lightning always follows
(a) a thunder
(b) rain pour
(c) the easiest path
(d) a straight path
Answer:
a thunder
Explanation:
It's because the difference in speed of light and sound
Light has speed about 3×10^8m/sSound has speed 344m/sSo we hear thunder later
Answer:
C
Explanation:
Lightning is a giant spark. A single stroke of lightning can heat the air around it to 30,000 degrees Celsius This extreme heating causes the air to expand at an explosive rate. The expansion creates a shock wave that turns to a booming sound wave, better known as thunder. Thunder & lightning occur at roughly the same time, although u see the flash of lightning before u hear the thunder. This is because light travels much faster than sound.Lightning always follows the easiest path. Lightning strikes buildings or projecting objects such as trees, poles, wires or building than larger, flatter surfaces because the material in them provide easier paths to the ground than the other. The primary target of lightning are lone buildings.Therefore, Thunder Follows The Easiest Part. And it is not (A) because Thunder Follows A Lightening Not Vice Versa.
3. Describe comets and their orbits in the solar system.
Comets have an extremely eccentric orbit around the Sun. They can travel hundreds of thousands of years through the solar system before returning to the Sun at perihelion. Comets, like all orbiting bodies, obey Kepler's Laws, which state that the closer they get to the Sun, the faster they move.
A comet is a dirty snowball many kilometers across that exists at a considerable distance from the Sun. However, when it gets closer to the Sun, the comet's surface warms up, causing its components to melt and vaporize, resulting in the comet's distinctive tail. The distance between the Earth and the Sun can be measured in comet tails.