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A large spool in an electrician's workshop has 65 m of insulation-coated wire coiled around it. When the electrician connects a battery to the ends of the spooled wire, the resulting current is 1.8 A. Some weeks later, after cutting off various lengths of wire for use in repairs, the electrician finds that the spooled wire carries a 2.9-A current when the same battery is connected to it. What is the length of wire remaining on the spool
Answer:
[tex]40.34\ \text{m}[/tex]
Explanation:
[tex]L_1[/tex] = Length of wire = 65 m
[tex]I_1[/tex] = Initial current = 1.8 A
[tex]I_2[/tex] = Final current = 2.9 A
We know
[tex]R\propto \dfrac{1}{I}[/tex]
and
[tex]R\propto L[/tex]
[tex]\dfrac{V}{I}\propto L\\\Rightarrow L\propto \dfrac{1}{I}[/tex]
so
[tex]\dfrac{L_2}{L_1}=\dfrac{I_1}{I_2}\\\Rightarrow L_2=\dfrac{I_1}{I_2}L_1\\\Rightarrow L_2=\dfrac{1.8}{2.9}\times 65\\\Rightarrow L_2=40.34\ \text{m}[/tex]
The length of the wire remaining on the spool is [tex]40.34\ \text{m}[/tex].
Explain retrograde motion and why it confused early astronomers as they viewed the motion of objects in the sky.
Answer:
Explanation:
Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is, the central object (right figure). It may also describe other motions such as precession or nutation of an object's rotational axis. Prograde or direct motion is more normal motion in the same direction as the primary rotates. However, "retrograde" and "prograde" can also refer to an object other than the primary if so described. The direction of rotation is determined by an inertial frame of reference, such as distant fixed stars.
Retrograde motion occurs when a planet far from another planet and from which it is seen rotates at lower speed, creating the impression that it is "retrograding" with respect to the other planet.
Early astronomers get confused as they viewed the motion in the sky because they tried to explain it in terms of the geocentric theory.
Let suppose that we have a planetary system formed by a star and two planets rotating uniformly around the star. Besides, we assume that both planets are rotating at different velocities, and that planet A is more far away from the star than planet B, then the velocity of the planet A relative to planet B is:
[tex]\vec v_{A/B} = \vec {v}_{A}- \vec {v}_{B}[/tex] (1)
A retrograde motion of planet A occurs when [tex]\|\vec v_{A/B}\|\ne 0[/tex] and if [tex]\|\vec v_{A}\| < \|v_{B}\|[/tex] at least. In other words, retrograde motion exists when speed of planet A is less than speed of planet B, creating the impression that planet A is "retrograding" with respect to planet B. This question is easy to solve and to explain by considering the star as an inertial framework, base of the heliocentrical model.
Early astronomers were confused and unable to explain the phenomenon due to their adherence to geocentrical model, which assumed the Earth was the center of the solar system.
We kindly invite to check this question on retrograde motion: https://brainly.com/question/13586212
Which one of the following is NOT acceleration
A.
a change in mass
B.
a change in direction
C.
an increase in velocity
D.
a decrease in velocity
Answer:
change in direction
Explanation:
ans maybe correct
Need help please help.
Answer:
below
Explanation:
that is the procedure above
Which of the following is the best
definition of tissue?
1 Pt
A
B
A. what organs are made of
B. your skin and muscles
C. parts of cells
D. a group of similar cells working together
E. None of the above
A meteor moving through space speeds up as it gets closer to Earth. What force causes the meteor's speed to increase the closer it gets to Earth?
PLS Help
Answer:
gravity
Explanation:
its hard to explain its one of the resons we do gravity assists for space probes and such the meteor will catch earths gravity and be pulled in by it if you look at sednas orbit as it gets closer to the sun it speeds up.
The force that causes the meteor's speed to increase as it gets closer to Earth is the gravitational force of earth.
What is meant by gravity ?Gravity is defined as the force by which a planet attracts another body towards its center.
Here,
The meteor was moving through space and the speed of the meteor started increasing as it moves closer to the earth.
This is because of the gravitational force of earth that is being exerted on the meteor. Gravitational force of earth is defined as the force of attraction that the earth exerts on another body in its gravitational field and draws them towards the center of the earth.
As the meteor moves towards the earth's , it gets accelerated by the earth's gravitational field such that the speed of the meteor increases and thus it attains more kinetic energy. As a result, the meteor moves faster when it gets closer to earth. This is because of the force of gravity of the earth.
Hence,
The force that causes the meteor's speed to increase as it gets closer to Earth is the gravitational force of earth.
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As a part of a laboratory investigation, Emily measured the volume of water in a graduated cylinder.Which of the choices correctly identifies the volume of water in the graduated cylinder?
Answer:
The choice that correctly identifies the volume of water in the graduated cylinder is option B i.e 35 mL
Explanation:
The complete question is
As a part of a laboratory investigation, Emily measured the volume of water in a graduated cylinder. Which of the choices correctly identifies the volume of water in the graduated cylinder? A. 38 mL B. 35 mL C. 37 mL D. 36.5 mL
The image for the question is attached herewith
Solution
The meniscus formed in this figure is a concave figure and in any concave figure the readings are taken from the bottom of the curve at eye level. In the attached image the bottom of the meniscus at the eye level is marked at 35 mL.
Hence the choice that correctly identifies the volume of water in the graduated cylinder is option B i.e 35 mL
1. KCIO3 -> KCI - O2. Reaction Type
Answer:
thermal decomposition reaction
Explanation:
The reaction 2KCIO₃ → 2KCI + 3O₂ is a decomposition reaction. It dissociates into its constituent elements.
Decomposition reactions involve the breakdown of a compound into two or more simpler substances. In this case, potassium chlorate (KCIO₃) decomposes into potassium chloride (KCI) and oxygen gas (O₂).
The balanced equation for the reaction is:
2KCIO₃ → 2KCI + 3O₂
This reaction is typically initiated by applying heat to KCIO₃, causing it to decompose into its constituent elements.
Therefore, The reaction 2KCIO₃ → 2KCI + 3O₂ is a decomposition reaction. It dissociates into its constituent elements.
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Question 6 (4 points)
An automobile is moving with a velocity of 25 m/ and weighs 15680 N. After braking for 6 seconds the velocity of the car is reduced to 14 m/s,
(Hint: Mind the signst)
a. What is the car's mass?
kg
b. What is the car's initial momentum?
kg m/s
What is the change in momentum of the car
kg m/s
d. What is the average braking force on the car?
N
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Time left for this
assement
50:56
A man lifts a 5 Newton bag of groceries
from the floor to the top of the countertop,
which is 1.1 meters tall. What is the work
done by this person in lifting groceries?
5
5.5
4.5
6
Answer:
5.5 J
Explanation:
W=F*D=5*1.1=5.5 J
What type of FORCE is GRAVITY?
a) PULL
b) PUSH
c) ENERGY
d) It is not a FORCE at all.
Answer:
It is (a) pull because when we are on earth we have gravity and it is pulling us down hope you have a great day!! :)
Explanation:
a force of 2N exerted on a block causes it to accelerate at 4m/s^2 over a frictionless surface. calc the mass of the block
the energy transfer that takes place by direct contact is called ____
Answer:
Conduction
Explanation:
The transfer of energy through matter by direct contact of particles is called. Conduction.
Answered by the ONE & ONLY #QUEEN herself aka #DRIPPQUEENMO!!!
HOPE THIS HELPED!!!
1200 calories isfind the change in internal energy of the system 1200 calories is removed from a gas held at constant volume give answers in kilojoule
What is the total distance blue covered throughout its journey?
A: 8s
B: 16
C: 8m
D: 16m
Ammonia is a common____?
Answer:
Base
Hope this helps! :)
anyone good at physics that can help me plss
Answer:
Where is the question?
-_-
-_-
-_-
-_-
-_-
I’m not sure how to determine the answer to this, I specifically need help with B.
Answer:
B. From positions A and D.
Explanation:
Types Of Energy Transfers
Heat can be transferred in three ways: by conduction, convection, and by radiation.
Conduction is the transfer of energy from one molecule to another by direct contact. Convection is the movement of heat by a fluid such as water or air. Radiation is the transfer of heat by electromagnetic waves.
Two point charges, the first with a charge of +3.50 10-8 C and the second with a charge of -4.50x10-6C, are separated by 25.0 cm. Find
the magnitude of the electrostatic force experienced by the positive charge.
a. 6.32 N
b. 2.27 N
c. 3.42 N
d. 4.45 N
Answer:
b. 2.27 N
Explanation:
Fe = (k)(Q1)(Q2) / d²
k ≈ 9 × 10⁹ N m² / C² [Coulomb's Constant] or 8.98 × 10⁹ (nearest hundredth).
q = particle charge [Coulombs; C]
d = distance [Meters; m]
Fe = Electrostatic force [Newtons; N]
________________________________
Fe = (9×10⁹)(3.5 × 10^(-8)(-4.5 × 10^(-6))/(.25)² N =
(9)(3.5)(-4.5) × (10^(9))(10^(-8))(10^(-6) / (.25)² N =
(9)(3.5)(-4.5) × (10^(9 - 8 - 6)) / (.25)² N =
(-141.75) × 10^(-5) / (.0625) N =
141.75 × 10^(-5) / (.0625) N
[opposite direction] =
(1.4175 × 10^(2)) × 10^(-5) / (.0625) N
[opposite direction] =
1.4175 × 10^(-3) / .0625 N
[opposite direction] =
1.4175 × 10^(-3) / 6.25 × 10^(-2) N =
14.175 / 6.25 N [opposite direction] =
2.268 N ≈ 2.27 N [opposite direction].
2-Write True(T) if the sentence is true. Write False(F) if the sentence is
false.
Momentum is a measure of the motion of a body equal to the product of its
mass and acceleration due to gravity.
Impulse is defined as the force times the time interval.
The tendency of an object to resist a change in motion is called Force
If the speed of an object is doubled, its momentum is multiplied by 2
Sudden change in momentum in a collision, results in a large force that can
cause injury.
Safety features of modern cars ensures that energy is not absorbed when vehicles
stop:
Crumple zones are built into cars to increase the duration of crashes.
Describe how rainforests are more diverse than arctic ecosystems. Give examples of ecological diversity, species diversity, and genetic diversity.
Answer:
Rainforests contain around 50% of all life on Earth and only take up 6% of the Earths surface area. It contains more species of plant and animals than any other ecosystem. It's climate and geography lend it to growing more plant life which sustains many small animals. The arctic is inhospitable to most species because of the extreme cold. It's food webs do not sustain themselves well as there are fewer species at the bottom the the chain. The genetic variations are greater at the equator than the arctic giving the organisms a greater chance to survive.
Rainforests are far more diverse than arctic ecosystems because of the amount of sunlight and the rain it receives throughout the year.
What are biomes?
Biomes can be defined as regions specified by particular biological and geographical communities that evolved because of the shared regional climate of that region.
Generally, there are mainly five major types of biomes those are forest desert grassland aquatic, and tundra.
Even though they only cover 6% of the planet's surface, rainforests are home to about 50% of all living. More plant and animal species may be found there than in any other habitat.
The high temperature of the arctic makes it uninhabitable for the majority of creatures. Because there are fewer species at the base of the food chain, its food webs are unable to support themselves.
Because there are more genetic variants around the equator than in the north, species there has a better chance of surviving.
Thus, rainforests are far more diverse than arctic ecosystems.
Learn more about biomes from here,
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5. A boy rides his skateboard 50 meters (m) West. Then he turns around
and goes 20 m East. What is the boy's DISPLACEMENT? *
Answer:
-30 m
Explanation:
50-20 but the direction is going west so it’s negative
Heating up a reaction speeds up the rate of the reaction because...
A. The particles collide more and have more energy
B. The particles collide less
C. The particles collide less and have less energy
D. The particles collide more with the correct orientation
Answer:
A.
Explanation:
more heat = heat energy becomes more kinetic energy = more particle collision
Answer:
the answer is A.There is increased kinetic energy making them collide more and speeds up the rate of reaction.
Explanation:
The tallest Ferris wheel in the world is located in Singapore. Standing 42 stories high and holding as many as 780 passengers, the Ferris wheel has a diameter of 150m and takes approximately 30 minutes to make a full circle. Determine the speed of the riders (in m/s) on the Singapore Flyer.
Answer:
The speed of the riders on the Singapore Flyer is approximately 0.262 m/s
Explanation:
The dimensions of the tallest Ferris wheel in the world are;
The diameter of the Ferris wheel, D = 150 m
The tine it takes the Ferris wheel to make a full circle, T = 30 minutes = 30 min × 60 s/min = 1,800 seconds
The angular velocity of the Ferris wheel, ω = 2·π/T
The linear velocity of the Ferris wheel, v = r·ω = The speed of the riders
Where;
r = The radius of the Ferris wheel = D/2
D = 150 m
∴ r = 150 m/2 = 75 m
∴ v = r·2·π/T
∴ v = 75 m × 2 × π/(1,800 s) ≈ 0.262 m/s
The speed of the riders on the Singapore Flyer, v ≈ 0.262 m/s
Question 7 (5 points)
(03.06 LC)
Losing
or fewer per week is a healthy rate of weight loss. (5 points)
Answer:
true?
Explanation:
What variable do you think made this airplane fly the farthest?
Answer:
How does the weight of the nose on a paper
airplane affect the distance it will travel
when measured in centimeters?
EXPERIMENT CONCLUSION: (Explain whether or
not your data supports, or fails to support your identified
prediction. Explain why, including facts and details!)
The distance did increase when I added 1 paper clip.
However, I was surprised that the distance decreased
when I added a second paper clip. I believe this
happened because the nose of the plane became too
heavy. When the plane was released, the nose of the
plane descended much quicker. I think the plane was
more balanced in weight when only 1 clip was on the
nose.
reason why ink is most likely to ooze out of a pen when one is up in an airplane
Answer:
Because in higher altitudes atmospheric pressure is low
Calculate the total momentum of the three-sphere system if the three spheres are swung at −1.0 msto the left.
Answer:
, pfx = pix + Jx.
Explanation:
The momentum principle tells us that impulse transfers momentum to an object.
If an object has 2 kgm/s of momentum, a 1 kgm/s impulse delivered to the object
increases its momentum to 3 kgm/s. That is, pfx = pix + Jx.
Just as we did with energy, we can represent this “momentum accounting” with a
momentum bar chart. For example, the bar chart of FIGURE 11.6 represents the ball
colliding with a wall in Figure 11.4. Momentum bar charts are a tool for visualizing
an interaction
kūna veikia 3N jėga kurios petys 20 cm. Koks jos momentas?
Answer:
0.6Nm
Explanation:
Moment = Force * perpendicular distance
Given
Force = 3N
Distance = 20cm = 0.2m
Get te moment
Moment = 3 * 0.2N
Moment = 0.6Nm
Hence her moment is 0.6Nm
explain the motion of a ball bearing falling through a viscous liquid
Answer:
its acceleration decrease because of the force acted upon by the viscous liquid