Answers
Answer:
The most common oxidation numbers for a given element
Related Questions
HURRY ILL GIVE 15 POINTS
Carla draws two circuit diagrams that connect the same components in different ways as shown which statement about the circuit is correct?
Answers
Circuit A is correct
Which of the following is a problem with the estimated age of the universe?
There are stars in our galaxy that appear to be over 15 billion years old.
The universe is shrinking, which makes it is impossible to tell how old it is.
There should be more supergiants if the universe is really about ten billion years old.
There are planets in other galaxies that are less than five billion years old.
Answers
Answer:
There are stars in our galaxy that appear to be over 15 billion years old.
Explanation:
The age of the universe is the time past since the big ban event as based on observations of the early state of the universe. The comic problem with the universe is that it's estimated to be older since the time of the big bang. It also represents a contrast with objects in the galaxies such as stars, planets that could not have been present.If a body of mass 2 kg is moving with a velocity of 30 m/s, then
on doubling its velocity the momentum becomes
a 30 kgm/s
b 90 kgm/s
C 120 kgm/s
d 60 kgm/s
HALPLPLPPLL
Answers
Answer:
d. 60
Explanation:
If a body of mass 2 kg is moving with a velocity of 30 m/s, then
on doubling its velocity the momentum becomes
a 30 kgm/s
b 90 kgm/s
C 120 kgm/s
d 60 kgm/s
HALPLPLPPLL
Answer:
120
Explanation:
which one hurry i need help pls dont get me wrong ..
Answers
Answer:
OPEN
Explanation:
An intentionally open circuit would be the circuit to the lights in the room that are turned off. There is no closed path available for the electricity to flow to the lights because the switch is in the "off" position which "opens" the path the electricity would normally flow through.
What is the definition of Heat Transfer
Answers
Answer:
Heat transfer is an engineering discipline that concerns the generation, use, conversion, and exchange of heat (thermal energy) between physical systems.
Explanation:
Answer:
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.
Explanation:
hope that helps
1. How would the forces from a header with such a light soccer ball cause a concussion? Draw
Two free body diagrams showing how the amount of peak force on the head would compare
to the amount of peak force on a soccer ball in a header that causes a collision.
Answers
Answer:
soccer when the ball hits an unprepared player in the head. He also gave examples of concussions occurring when players accidentally knock their heads into other players while attempting to head the ball, particularly if they are attempting to flick the ball backwards.
Explanation:
Heading in soccer can increase your risk of concussions. Over time, repeated subconcussive injuries can also accumulate and cause brain damage.
So this helicopter pilot dropped me in the middle of an absolutely smooth frictionless
lake. He thought it was really funny. The only thing the pilot let me take is a bowling
ball. I tried to claw my way to the shore but was unable to get any horizontal force on
the super slippery zero friction ice. Explain how I can get to shore and why it will
work before I freeze to death. This test is about momentum. I wonder if my solution
has anything to do with that ...
Answers
The FitnessGram™ Pacer Test is a multistage aerobic capacity test that progressively gets more difficult as it continues. The 20 meter pacer test will begin in 30 seconds. Line up at the start. The running speed starts slowly, but gets faster each minute after you hear this signal. [beep] A single lap should be completed each time you hear this sound. [ding] Remember to run in a straight line, and run as long as possible. The second time you fail to complete a lap before the sound, your test is over. The test will begin on the word start. On your mark, get ready, start.
A 300-g chunk of ice (of density 0.900 g/cm3) is placed in a water bucket. A 20.0-g rock, with a volume of 2.00 cm3, is placed on top of the ice before water is filled to the top. When the ice melts and the rock drops to the bottom of the buckt, how much water spills out or needs to be added to maintain full level? Ignore the possible dependence of the densities of ice and water on temperature.
Answers
Answer:
18 cm³ of water
Explanation:
The correct procedure and explanation is in the picture attached. If you have any doubts, feel free to leave in the comments.
Hope this helps
How does a generator use the effect you noticed in the pickup coil to generate electrical energy? What energy transformations are taking place? Why does a generator make alternating current? What change would have to be made to make direct current?
Answers
Answer:
Movement of Electrons in opposite direction of the rotation of the pickup coil leads to the direction of Electrical energy ( Alternating current ).
Explanation:
For a Generator to generate electricity, Electrons that is found in the rotating coil of the Generator will experience some sort of force that makes them to start moving in a direction that is perpendicular to the direction of the rotating/pickup coil found in the Generator.
The conversion of mechanical energy (Rotation of the pickup coil ) to electrical energy takes place in the Generator
The generator makes an alternating current because electrons move in opposite direction of the rotating coil
In other to generate a Direct current using a generator we have to replace the slip rings with commutator.
A scientist wants to create a new material using nanotechnology. In which size range will she be working? 1 nm to 100 nm 1 to 10,000 nm 100 to 1000 nm 100 to 10,000 nm
Answers
Answer:
I believe it’s A
Explanation:
Answer:
A is correct (1 nm to 100 nm)
Explanation:
I just took the exam
An object of mass 25kg is falling from the height h=10 m. calculate
a. The total energy of an object at h=10m.
b. Potential energy of the object when it is at h= 4m
c. Kinetic energy of the object when it is at h= 4m
d. What will be the speed of the object when it hits the ground?
Answers
Answer:
a=2500J,b=1000K,c=1000J,d=14.142m/s
Explanation:
V²=U²+2gh
V²=0 + 2×10×10=200m/s
a).kinetic energy=(1/2)mv²=(1/2)25×200=2500
potential energy=mgh
p.e=25×10×10=2500J
pe+ke=2500+2500=5KJ
b).mgh=25×10×4=1000J
c). V²=U²+2gh
V²=0+2×10×4
V²=80
kinetic energy=(1/2)mv²
=(1/2)25×80
=1KJ
d). From my first paragraph V²=200
V=√200
V=14.142m/s
explain why the lamp does not light when the input to the transformer is directed current
Answers
Answer:
Direct current(DC) has no time varying field because current is constant as well as there is no relatively motion between coil and core(magnetic circuit) of the transformer. So there is no induced emf in secondary coil of the transformer. Tom Mounts, field engineer, and electronics technician.
Explanation:
can i have brainly if right
A loudspeaker, mounted on a tall pole, is engineered to emit 75% of its sound energy into the forward hemisphere, 25% toward the back. You measure an 85 dB sound intensity level when standing 3.5 m in front of and 2.5 m below the speaker. What is the speaker’s power output?
Answers
Answer:
"0.049 W" is the correct answer.
Explanation:
According to the given question,
[tex]r = \sqrt{(3.5)^2+(2.5)^2}[/tex]
[tex]=\sqrt{8.5}[/tex]
[tex]SL=85[/tex]
As we know,
⇒ [tex]SL=10 \ log(\frac{I}{I_o} )[/tex]
[tex]85=10 \ log(\frac{I}{10^{-12}} )[/tex]
[tex]I=3.162\times 1^{-4} \ W/m^2[/tex]
Now,
⇒ [tex]P_{front} = I(2\pi r^2)[/tex]
[tex]=(3.162\times 10^{-4})(2\pi\times 18.5)[/tex]
[tex]=0.0368 \ W[/tex]
[tex]=0.75 \ P[/tex]
or,
[tex]=0.049 \ W[/tex]
The total resistance of a series circuit is 15.0 ohms what is the second resistance of the first resistance is 10.0 ohms?
A. less than 5.0 ohms
B. 5.0 ohms
C. 15 ohms
D. 25 ohms
Answers
At what rate is thermal energy being generated in the 2R-resistor when ε = 12 V and R = 3.0 Ω?
Answers
Answer:
6 W
Explanation:
From the given information:
The resistance in Parallel for 2R is:
[tex]R_p = \dfrac{2R\times 2R}{2R+2R} \\ \\ R_p= R[/tex]
The equivalent resistance:
[tex]R_{eq} = R_p + R = 2R[/tex]
[tex]R_{eq} = 2(3)[/tex]
[tex]R_{eq} = 6 \ \ ohms[/tex]
The current through the circuit in R is:
[tex]= \dfrac{12}{R+R} \\ \\ = \dfrac{12}{2\times 3} \\ \\ = 2 A[/tex]
The current through the circuit in 2R is:
[tex]I_2R = (2A) \times \dfrac{2R}{2R+2R}[/tex]
[tex]I_2R = 2A \times \dfrac{1}{2} \\ \\ I_2R = 1A[/tex]
Finally, the thermal energy:
[tex]P_{2R} = (1)^2 (2R)[/tex]
[tex]P_{2R} = (1)^2 (2\times 3)[/tex]
[tex]P_{2R} = 6W[/tex]
40 points! Will give brainliest!
Which of the following describes an advantage of AC electricity over DC electricity?
A) AC is found in most low voltage operations.
B) AC is provided as strong, short bursts of electricity.
C) AC can be transported over long distances.
D) AC can be used is small electronic devices.
Answers
5. A ball weighing 10 kg rolls 200 m down a frictionless incline with a 50 degree angle to the horizontal. If the ball’s initial velocity was 0 m/s, how much does the mechanical energy of the system change by the time the ball reaches its destination? A) It increased by 12%. B) It increases by 58%. C) It decreases by 12%. D) It does not change.
Answers
Answer:
D) It does not change
Explanation:
Since there is no friction in the inclined plane. Therefore, there is no loss in the total mechanical energy of the system. So according to the law of conservation of energy we can write:
Total Mechanical Energy at Start = Total Mechanical Energy at End + Frictional Loss
Total Mechanical Energy at Start = Total Mechanical Energy at End + 0
Total Mechanical Energy at Start = Total Mechanical Energy at End
It means there is no change in the total mechanical energy of the system.
Therefore, the correct option is:
D) It does not change
A truck was carrying a substance in a tank. The molecules of that substance were moving away from each other. The truck parked overnight in a place where energy transferred out of the substance. In the morning, the substance was a gas. How were the molecules moving in the morning? Explain why the molecules were moving that way after energy was transferred out of them.
(Make it ask long as you need)
Or (short)
Answers
Answer:
In the morning the molecules were moving away from each other with a smaller speed than when the truck was carrying the substance.
Explanation:
The Nardo ring is a circular test track for cars. It has a circumference of 12.5 km. Cars travel around the track at a constant speed of 100 km/h. A car starts at the easternmost point of the ring and drives for 30 minutes at this speed.
Required:
a. What distance, in km, does the car travel?
b. What is the magnitude of the car's displacement, in km, from its initial position?
c. What is the speed of the car in m/s?
Answers
Answer: 50 km, 0, 27.78 m/s
Explanation:
Given
Circumference of the track is [tex]12.5\ km[/tex]
Speed of car is [tex]100\ km/h[/tex]
Car drives for [tex]30\ \text{minute}\ or\ 0.5\ hr[/tex]
(a)Distance traveled is
[tex]\Rightarrow D=100\times 0.5\\\Rightarrow D=50\ km[/tex]
(b)displacement of the car
It can be observed that 12.5 is a multiple of 50, that is, 50 km can be interpreted as 4 complete rounds of the track.
Therefore, the displacement of the car is zero.
(c)To convert kmph to m/s, multiply the entity by [tex]\frac{5}{18}[/tex]
[tex]\Rightarrow 100\times \dfrac{5}{18}\\\\\Rightarrow 27.78\ m/s[/tex]
Find the magnitude of the free-fall acceleration at the orbit of the Moon (a distance of 60RE from the center of the Earth with the radius of RE). Use the gravitational acceleration on the surface of the Earth is 9.8m/s2.
Answers
Answer:
The magnitude of the free-fall acceleration at the orbit of the Moon is [tex]2.728\times 10^{-3}\,\frac{m}{s^{2}}[/tex] ([tex]\frac{2.784}{10000}\cdot g[/tex], where [tex]g = 9.8\,\frac{m}{s^{2}}[/tex]).
Explanation:
According to the Newton's Law of Gravitation, free fall acceleration ([tex]g[/tex]), in meters per square second, is directly proportional to the mass of the Earth ([tex]M[/tex]), in kilograms, and inversely proportional to the distance from the center of the Earth ([tex]r[/tex]), in meters:
[tex]g = \frac{G\cdot M}{r^{2}}[/tex] (1)
Where:
[tex]G[/tex] - Gravitational constant, in cubic meters per kilogram-square second.
[tex]M[/tex] - Mass of the Earth, in kilograms.
[tex]r[/tex] - Distance from the center of the Earth, in meters.
If we know that [tex]G = 6.674\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}}[/tex], [tex]M = 5.972\times 10^{24}\,kg[/tex] and [tex]r = 382.26\times 10^{6}\,m[/tex], then the free-fall acceleration at the orbit of the Moon is:
[tex]g = \frac{\left(6.674\times 10^{-11}\,\frac{m^{3}}{kg\cdot s^{2}} \right)\cdot (5.972\times 10^{24}\,kg)}{(382.26\times 10^{6}\,m)^{2}}[/tex]
[tex]g = 2.728\times 10^{-3}\,\frac{m}{s^{2}}[/tex]
A series circuit is set up with an AA battery along with an mystery material and ammeter; however, there’s no current passing through.
A.Insulator
B.Conductor
C.Semiconductor
Answers
Answer:
A. Insulator
Explanation:
Since there is no current passing through at all.
In a single-slit experiment, the slit width is 150 times the wavelength of the light.
What is the width (in mm) of the central maximum on a screen 2.6 m behind the slit?
I have tried:
y=[(1+1/2)(lambda)(2.6m)] / (150lambda)
to bring me to
y=[(1.5)(2.6)] \ (150)
giving me a y value in mm of 26
Answers
B wit. How ir
Magnets on the tracks
How can levitating trains support the claim that magnetic fields exist between objects exerting magnetic force on each other even when there is no physical contact?
Answers
Answer:
Explanation: They levitate sort of because when to opposite forces of magnets cant go together they repelA bat emits a sound at a frequency of 30.0 kHz as it approaches a wall. The bat detects beats such that the frequency of the echo is 900 Hz higher than the frequency the bat is emitting. The speed of sound in air is 340 m/s at emits a sound at a frequency of 30.0 kHz
(a) What is the speed of the bat?
(b) What is the wavelength of the sound that the bat hears15?
Answers
Answer:
a) the speed of the bat is 5.02 m/s
b) the wavelength of the sound that the bat hears is 0.011 m
Explanation:
Given the data in the question;
Frequency of sound emitted by a bat f = 30.0 kHz = 30000 Hz
detected frequency by the bat δf = 900 Hz
speed of sound in air c = 340 m/s
Let speed of sound and speed of bat be c and [tex]v_s[/tex] respectively;
Now, frequency of the sound that is coming from the bat towards the wall due to DROPPLER EFFET will be;
f₁ = ( c / ( c - [tex]v_s[/tex] ) )f ----- let this be equ 1
Also, frequency does not change after deflection. The bat becomes an observer as the dropper is shifted because the reflected sound wave is coming towards it;
Hence, Doppler shifted frequency will be;
f₂ = ( (c + [tex]v_s[/tex] ) / c )f₁
from equ 1, f₁ = ( c / ( c - [tex]v_s[/tex] ) )f, so we substitute
f₂ = ( (c + [tex]v_s[/tex] ) / c ) × ( c / ( c - [tex]v_s[/tex] ) )f
f₂ = ( (c + [tex]v_s[/tex] ) / ( c - [tex]v_s[/tex] ) )f
∴ beat frequency will be;
δf = f₂ - f = ( (c + [tex]v_s[/tex] ) / ( c - [tex]v_s[/tex] ) )f - f
δf = ( 2[tex]v_s[/tex] / c - [tex]v_s[/tex] )f
δf = ( 2[tex]v_s[/tex] / c - [tex]v_s[/tex] )f
2f/δf = c - [tex]v_s[/tex] / [tex]v_s[/tex]
2f/δf = c/[tex]v_s[/tex] - [tex]v_s[/tex] / [tex]v_s[/tex]
2f/δf = c/[tex]v_s[/tex] - 1
c/[tex]v_s[/tex] = 2f/δf + 1
[tex]v_s[/tex] = c / (2f/δf + 1)
now, we substitute in our values;
[tex]v_s[/tex] = 340 / ((2×30000 / 900 ) + 1)
[tex]v_s[/tex] = 340 / (66.6666 + 1)
[tex]v_s[/tex] = 340 / 67.6666
[tex]v_s[/tex] = 5.02 m/s
Therefore, the speed of the bat is 5.02 m/s
b) the wavelength of the sound that the bat hears
frequency of reflected wave is;
f₂ = f + δf = 30000 + 900 = 30900 Hz
λ₂ = c / f₂
we substitute
λ₂ = 340 / 30900
λ₂ = 0.011 m
Therefore, the wavelength of the sound that the bat hears is 0.011 m
What is the net force on a skydiver falling with a constant velocity of 0 m/s downward?
Answers
Based on the number on the fuse, what do you think is the maximum current allowed in this circuit?
Answers
Answer:
0.3 A
Explanation:
Build the circuit attached. Make sure the switch is turned off as you build the circuit. Set the Selected battery voltage to 10 volts.
A. Based on the number on the fuse, what do you think is the maximum current allowed in this circuit?
Solution:
A fuse is a safety device which is used in circuits for preventing very high currents which can cause overloading or start a fire. A fuse is made up of a low resistance thin piece of metal such that the flow of high current can cause the metal to melt leading to an open circuit. A fuse lets current flow up to a maximum value before it melts and the circuit will be broken.
From the image attached, since the maximum rating of the fuse is 0.3 A, hence the maximum current that can flow through the circuit is 0.3 A.
Which is one way to determine whether a reaction was a chemical reaction or a nuclear reaction?
Answers
Answer:
Check how much energy was released during the reaction or check for a change in total mass
Describe the formation of galaxies.
Answers
Today's cosmologists assume that matter was not uniformly distributed in the universe after the Big Bang. Dense places attract more matter than the surrounding area according to their gravitational forces. Over the course of billions of years, these gas agglomerations eventually led to the formation of the galaxies we see today.
Does a ball rolling on an inclined plane have the same acceleration on the way up as it does on the way down?
Answers
Answer:
No, it does not.
Explanation:
According to the Law of Gravitation, something going down has more kinetic energy than something going up because it attracts pressure from around it when going down. When it goes up, it has less gravitational force and inertia also stops the ball from rolling upward. Therefore, without the amount of kinetic energy, it will not have the same amount of acceleration.
Consider a father pushing a child on a playground merry-go-round. The system has a moment of inertia of 84.4 kg.m^2. The father exerts a force on the merry-go-round perpendicular to its radius to achieve an angular acceleration of 4.44 rad/s^2.
Required:
a. How long (in s) does it take the father to give the merry-go-round an angular velocity of 1.53 rad/s? (Assume the merry-go-round is initially at rest.)
b. How many revolutions must he go through to generate this velocity?
c. If he exerts a slowing force of 270 N at a radius of 1.20 m, how long (in s) would it take him to stop them?
Answers
Answer:
Explanation:
Given that:
the initial angular velocity [tex]\omega_o = 0[/tex]
angular acceleration [tex]\alpha[/tex] = 4.44 rad/s²
Using the formula:
[tex]\omega = \omega_o+ \alpha t[/tex]
Making t the subject of the formula:
[tex]t= \dfrac{\omega- \omega_o}{ \alpha }[/tex]
where;
[tex]\omega = 1.53 \ rad/s^2[/tex]
∴
[tex]t= \dfrac{1.53-0}{4.44 }[/tex]
t = 0.345 s
b)
Using the formula:
[tex]\omega ^2 = \omega _o^2 + 2 \alpha \theta[/tex]
here;
[tex]\theta[/tex] = angular displacement
∴
[tex]\theta = \dfrac{\omega^2 - \omega_o^2}{2 \alpha }[/tex]
[tex]\theta = \dfrac{(1.53)^2 -0^2}{2 (4.44) }[/tex]
[tex]\theta =0.264 \ rad[/tex]
Recall that:
2π rad = 1 revolution
Then;
0.264 rad = (x) revolution
[tex]x = \dfrac{0.264 \times 1}{2 \pi}[/tex]
x = 0.042 revolutions
c)
Here; force = 270 N
radius = 1.20 m
The torque = F * r
[tex]\tau = 270 \times 1.20 \\ \\ \tau = 324 \ Nm[/tex]
However;
From the moment of inertia;
[tex]Torque( \tau) = I \alpha \\ \\ Since( I \alpha) = 324 \ Nm. \\ \\ Then; \\ \\ \alpha= \dfrac{324}{I}[/tex]
given that;
I = 84.4 kg.m²
[tex]\alpha= \dfrac{324}{84.4} \\ \\ \alpha=3.84 \ rad/s^2[/tex]
For re-tardation; [tex]\alpha=-3.84 \ rad/s^2[/tex]
Using the equation
[tex]t= \dfrac{\omega- \omega_o}{ \alpha }[/tex]
[tex]t= \dfrac{0-1.53}{ -3.84 }[/tex]
[tex]t= \dfrac{1.53}{ 3.84 }[/tex]
t = 0.398s
The required time it takes= 0.398s