Answer: Se presentan en equilibrio a nivel atómico y/o molecular
Explanation: Sólo los iones presentan campo eléctrico pero no son estables en la naturaleza ya que tienden a encontrar al ion de carga opuesta con el cual equilibrar la carga. El estado de equilibrio de un cuerpo o materia se da al tener idéntica cantidad de electrones (-) que de protones (+)-
Two uniform bars of the same dimensions are constructed from the same material. One bar has five evenly spaced holes through it and the second bar has only two holes. In these cases, the bars are slid over vertical pegs and rest on a horizontal surface, where friction between the bar and the surface is negligible. The two bars are each pulled by
horizontal forces of equal magnitude F from their right end as shown above. The bars' resulting angular accelerations are recorded.
Is the magnitude of the initial angular acceleration of the bar in case 1 larger than, smaller than or equal to the magnitude of the initial angular acceleration of the bar in Case 2? Explain your reasoning.
Solution :
The angular acceleration, [tex]$\alpha$[/tex] is obtained from the equation of the [tex]$\text{Newton's second law}$[/tex] of rotational motion,
Thus,
[tex]$\tau = F \times d$[/tex]
or [tex]$\tau = I \times \alpha$[/tex]
where [tex]$\tau$[/tex] is torque, F is force, d is moment arm distance, I is the moment of inertia
Thus, [tex]$\alpha=\frac{(F\times d)}{I}$[/tex]
Now if the force and the moment arm distance are constant, then the [tex]\text{angular acceleration is inversely proportional to the moment of inertia.}[/tex]
That is when, F = d = constant, then [tex]$\alpha \propto \frac{1}{I}$[/tex] .
Thus, moment of inertia, I is proportional to mass of the bar.
The mass is less for the bar in case (1) in comparison with that with the bar in case (2) due to the holes that is made in the bar.
Therefore, the bar in case (1), has less moment of inertia and a greater angular acceleration.
A sound wave takes 0.2 seconds to travel 306 meters.
What is the speed of sound in this material? Through
which of the materials in Figure 24.23 is the wave
traveling?
Answer:
1530 m/s
Explanation:
Given that :
Speed = distance / time
Travel time take = 0.2 s
Distance covered = 306 metres
The speed of sound in the material :
Speed = distance / time = 306 m / 0.2
Speed = 1530 m/s
A.All three bulbs will go out
B.Bulbs 2 and 3 will go out, but bulb 1 will remain lit
C. All three bulbs will go out
D. Bulb 3 will go out, but bulbs 1 and 2 remain lit
Answer:
(D)
Explanation:
When switch C is opened then, Current is not flowing across 3 So bulb 3 will go out.
But current is flowing across 1 and 2 bulb because their switch is closed
therefore bulb 1 and 2 will remain it.
Hence, option (D) will be correct.
Hello all, can you please answer this? I am struggling with this. I need this by tommorow. Question is below:
Light waves of frequency 6 x 10^14 Hz have a wavlength of 3.75 x 10^-7 m in water. What is their speed in water?
[tex]c_{water} = 2.25\times 10^{8}m/s[/tex]
Explanation:
The speed of light in any medium is given by
[tex]c = \lambda \nu[/tex]
where [tex]\lambda[/tex] is the wavelength and [tex]\nu[/tex] is the frequency. In water,
[tex]c_{water} = \lambda_{water} \nu[/tex]
[tex]\:\:\:\:\:\:\:\:= (3.75\times 10^{-7}\:m)(6\times 10^{14})\:Hz[/tex]
[tex]\:\:\:\:\:\:\:\:= 2.25\times 10^{8}\:m/s[/tex]
A meter 0.0525 m from a wire measures a magnetic field of 7.14 x 10-6 T. How much current flows through the wire?
Answer:
[tex]I=1.9A[/tex]
Explanation:
From the question we are told that:
Meter distance [tex]d=0.0525[/tex]
Magnetic field [tex]B=7.14*19^{-6}T[/tex]
Generally the equation for Magnetic field B is mathematically given by
[tex]B =\frac{\mu *I }{2* \pi r}[/tex]
[tex]7.14*19^{-6}T =\frac{ 1.26 *10^{-6} *I }{2* 3.142*0.0525}[/tex]
Where
Constant[tex]\mu=1.26 *10^{-6}[/tex]
[tex]I=1.9A[/tex]
Therefore
The Current through the wire is
[tex]I=1.9A[/tex]
Answer: 1.87
Explanation:
acellus
Um comentarista de futebol certa vez comentou:"A bola bateu na trave e voltou duas vezes mais forte". Sabendo que quando a bola atinge a trave ela acerta com uma força chamada de ação e a outra trave acerta com outra força chamada de reação explique porque a frase documentalista soa errada.
Answer:
Por ela ter batido na trave, não tem como voltar 2x mais forte, por que toda ação correspondente a uma reação de igual intensidade, mas que atua no sentido oposto
Explanation:
A ship anchored at sea is rocked by waves that have crests Lim apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Question: A ship anchored at sea is rocked by waves that have crests 100 m apart the waves travel at 70m/S, at what frequency do the waves reach the ship?
Answer:
0.7 Hz
Explanation:
Applying,
v = λf............... Equation 1
Where v = velocity of the wave, f = frequency fo the wave, λ = wavelength of the wave
make f the subject of the equation
f = v/λ................. Equation 2
From the question,
Given: v = 70 m/s, λ = 100 m ( distance between successive crest)
Substitute these values into equation 2
f = 70/100
f = 0.7 Hz
Hence the frequency at which the wave reach the ship is 0.7 Hz
an object that is 15 cm tall is placed 44 cm in front of a diverging lens. A virtual image appears -14cm in front of the lens. determine the focal length of the lens .
SHOW YOUR WORK.
A) 0.09cm
B)-20.53cm
C)10.6cm
D)-0.04cm
Answer:
The correct option is (b).
Explanation:
Given that,
The height of the object, h = 15 cm
Object distance, u = -44 cm
Image distance, v = -14 cm
We need to find the focal length of the lens. Using the lens formula.
[tex]\dfrac{1}{f}=\dfrac{1}{v}-\dfrac{1}{u}\\\\\dfrac{1}{f}=\dfrac{1}{(-14)}-\dfrac{1}{(-44)}\\\\f=-20.53\ cm[/tex]
So, the focal length of the lens (-20.53 cm).
An elevator of 3 × 10^4N is raised to a height of 100m in 20s . The work done by electric motor is equivalent to ?
Answer:
we neglect the time data
Show your work please
Answer:
[tex] V = U + at[/tex]
Explanation:
Given the following data;
Initial velocity = 0 (since the stone is starting from rest).
Final velocity = 32 m/s
Acceleration = g = 10 m/s²
Time = 3.2 seconds
To show that the speed of the stone when it hits the ground is 32 m/s, we would use the first equation of motion;
[tex] V = U + at[/tex]
Where;
V is the final velocity. U is the initial velocity. a is the acceleration. t is the time measured in seconds.Substituting into the formula, we have;
[tex] 32 = 0 + 10*3.2[/tex]
[tex] 32 = 0 + 32 [/tex]
[tex] 32 = 32 [/tex]
Proven: 32 m/s = 32 m/s
The specitic heat capacity of oxygen is 918 J/kg °C. The specific heat capacity of water is 4181 J/kg °C. Which substance will require more energy to raise its temperature by 1°C?
Answer:
Water
Explanation:
Given the specific heat of oxygen is 918J/kg °C and the specific heat of water is 4181 J/kg °C.
Consider 1Kg mass of each substance.
Now 1 Kg of oxygen needs 918 J of energy to raise its temperature by 1 °C
Also, 1 Kg of water needs 4181 J of energy to raise its temperature by 1 °C.
Clearly water requires more energy when compared to oxygen.
Basically, specific heat capacity is the amount of energy required to raise the temperature of a 1 kg body by 1 °C.
The three scientists credited with using all available data and correctly determing the sturcture of dna from many years of previous work are
Answer:
James Watson, Francis Crick, and Maurice Wilkins
Explanation:
The three scientists that used the available data ( x-ray images of DNA provided by Rosalind Franklin) to correctly determine the structure of DNA are : James Watson, Francis Crick, and Maurice Wilkins.
These scientists discovered the structure of DNA in 1953 and they received, and they receive a Nobel Prize in Physiology or Medicine for their discovery
the length of second hand of clock is 14cm, an ant sits on the top of second hand. find the following
i) speed of ant
ii) distance covered by ant in 150 seconds
iii) displacement in 150 seconds
Answer:
The answer is below
Explanation:
i) Since the length of the second clock (radius) is 14 cm = 0.14 m, the distance covered by the second hand in one revelution is:
Distance covered = 2πr = 2π(0.14) = 0.88 m
The time taking to complete one revolution = 60 seconds, hence;
Speed = distance covered in one revolution / time take o complete a revolution
Speed = 0.88 m / 60 s = 0.0147 m/s
ii) Distance covered in 150 s = speed * 150 s = 0.0147 * 150 = 2.2 m
iii) Displacement in 150 seconds = distance from initial position to final position
At 150 s, the hand has covered 2 revolutions and moved 30 s. Hence:
Displacement in 150 seconds = speed * 30 s = 0.0147 * 30 = 0.44 m
Which instrument changes kinetic energy into electrical energy?
electric motor
hair drier
electric bell
dynamo
Answer:
Dynamo
Explanation:
Dynamo started to rotate which is known as kinetic energy.When dynamo is in running it produces electricity.dynamo specially used for generating electricity.
ssooeorkgogogoogkrorooror
Answer:
ssooeorkgogogoogkrorooror
Explanation:
a mass of 2kg has a kinetic energy of 16J.what is the momentum of the body?
Explanation:
mass - 2kg
energy - 16 j
2
k.e- 1/2mv
2
16j=1/2×2×v
2
16×2/2=v
2
16=v
√16=v
V=4m/s
then momentum =mv
= 2×4
= 8 kgm/s
the force acting normally per unit area on the surface of the body is known as
The equivalent resistances of two wires connected in series and in parallel are 25 ohm and 4 ohm respectively. Calculate the resistance of each wire.
Answer:
5ohms and 20ohms
Explanation:
Let the resistance of each wire be R1 and R2, if the equivalent resistance in series is 25 ohms, then;
R1 + R2 = 25 ...1
If the equivalent in parallel is 4 ohm, then;
1/R1 + 1/R2 = 1/4
R2+R1/R1R2 = 1/4
Cross multiply
4(R2+R1) = R1R2 ...2
From 1;
R1 = 25 - R2 ... 3
Substitute 3 into 2
4(R2+25-R2) = (25-R2)R2
4(25) = (25-R2)R2
100 = 25R2 - R2²
R₂² -25R₂+100 = 0
R₂² -20R₂-5R₂+100 = 0
R₂(R₂-20)-5(R₂-20) = 0
(R₂-5)(R₂-20)=0
R₂ = 5 or 20
Since R₁ = 25-R₂
R₁ = 25 - 5
R₁ = 20
Hence the resistances are 5ohms and 20ohms
A circuit diagram with a power source labeled 12 V is connected to 3 resistors in series. The resistors are labeled 1.0 Ohms, 2.0 Ohms, and 3 Ohms. Calculate the equivalent resistance in the circuit shown.
0.55 Ω
1.8 Ω
2.0 Ω
Its A "0.55" I guessed and got it right
Answer:
there it is fella u were right with ur answer
2. In a chemical reaction
a) The atoms of the reactants always stay together to form the products
b) The atoms of the reactants unbond, rearrange, and then rebond to form the products
c) New atoms are formed which combine to make the products
d) Some atoms disappear while others multiply to form the products
Answer:
what I think in my opinion is B
HELP
Question 1 of 25
A boy throws a ball straight up with a speed of 21.5 m/s. The ball has a mass
of 0.19 kg. How much gravitational potential energy will the ball have at the
top of its flight? (Assume there is no air resistance.)
O A. 48.5J
B. 41.2J
O C. 43.9 J
O D. 37.5J
Answer:
Explanation:
Although there is absolutely NO regard for significant digits, I can help you with this, nonetheless.
The equation for Potential Energy is PE = mgh. We have everything but the height of the ball. We have to solve for that using a one-dimensional motion equation:
v² = v₀² + 2aΔx, where Δx is our displacement (the height we need for PE). Filling in and keeping in mind that at the max height of parabolic travel, the final velocity of the object is 0:
0 = (21.5)² + 2(-9.8)Δx and
0 = 462.25 - 19.6Δx and
-462.25 = -19.6Δx so
Δx = 23.58 m. Using this as the h in our PE equation:
PE = .19(9.8)(23.58) so
PE = 43.9 J, choice C.
Amigos necesito que me ayuden a resolver esta gráfica :').
Answer:
ANO BA TO?(;-;)
Explanation:
miss the rage??
What effect does the distance between Earth and the Sun have on Earth’s seasons?
Answer:
So actually, it is not so much the distance at a particular time that affects the seasons. It is a common misconception. It is in-fact the earths tilt. When we rotate around the sun, due to our tilt, the North and South of earth have different seasons. This is because when light is shining on to earth, because of Earths tilt, on one half the light shines more directly and on the other it scatters thus the different temperatures, causing season. Hope this helps.
A person skateboards at 3.25 m/s for 55.0 s. How far did he travel?
A 1000 kg car accelerates from rest at a rate of 10 m/s² for 3 seconds. A) what is the final velocity of the car?
Answer:
Explanation:
We don't need the mass of the car in the equation to solve for final velocity, since the values given for the acceleration and the time it took to accelerate to that velocity are given. The equation we need is the one for acceleration, which is
[tex]a=\frac{v_f-v_0}{t}[/tex] We are solving for final velocity, we know the initial velocity is 0 (starting from rest), and the time to complete this acceleration (10 m/s/s) is 3 seconds:
[tex]10=\frac{v_f-0}{3}[/tex] which is the same thing as saying
[tex]10=\frac{v}{3}[/tex] so
v = 30 m/s
At 10-10 s during the evolution of the universe,______
formed, which are elementary particles that make
up protons and neutrons
What’s in the blank ?
Answer: Quarks
Explanation:
Quarks are the elementary particles that make up protons and neutrons. If you want to be more specific, there's six types, but overall, it's just quarks.
What is the mass of a cart that has an acceleration of 10m/s^2 when a net force of 2000 N is applied to it?
Please I need the answer...
Answer:
200kg is the answer to the question
A parallel network consist of three resistors 4 ohm, 8 ohm and 16 ohm .If the current in 8 ohm resistor is 3 A then what are the currents in other resistors
Answer:
If the resistors are in parallel they must all experience the same voltage drop.
R * I = V
8 * 3 = 24 V (if i is 3 amps)
24V / 4 ohm = 6 amps
24V / 16 ohm = 1.5 amps
A bus travels with a constant speed of 48km/h. How long will it take to travel 60km?
Answer:
It will take 1 hr and 15 mins.
Explanation:
Let's look at the speed equation:
s=d/t
We want to find the time, and we have the speed and the distance, so we rearrange the equation. t will be on one side and s and d will be on the other side.
t=d/s
t=60km/(48km/h)
t=1.25h
would volcanic activity have a noticable impact on climate over the next 50 years?
Answer:
yes
Explanation:
The gases and dust particles thrown into the atmosphere during volcanic eruptions have influences on climate. ... Volcanoes have also caused global warming over millions of years during times in Earth's history when extreme amounts of volcanism occurred, releasing greenhouse gases into the atmosphere.