Answer:
A
Explanation:
Consider a question you may not have considered before. Suppose you have a mole of sodium in a container that contains nothing that it will react with. A mole of anything is 6.02 * 10^23 (in this case atoms).
Suppose that every one of those atoms has contributed 1 electron to something.
Do you think it would be safe to touch the container knowing that there are 6.02 * 10^23 positive charges all eager to get another electron, because they don't like repelling each other.
Safe or not? I'll give you a hint. A lightning bolt does not contain anywhere near 6.02*10^23 charges. No where near.
So -- since you never get a shock from just touching anything, There must not be electrons or ions present.
The answer is A
iv. An object is 14 cm in front of a convex mirror. The image is 5.8 cm behind the mirror. What is the focal length of the mirror? A. 4.1cm B. 8.2 cm C. 9.9 cm D. 20 cm
Answer:
C. 9.9 cm
Explanation:
The location of the object, u = 14 cm
The location of the image, v = 5.8 cm
The focal length of the mirror, f = Required
The mirror formula for a convex mirror is given as follows;
[tex]\dfrac{1}{u} -\dfrac{1}{v} = -\dfrac{1}{f}[/tex]
Therefore, we get;
[tex]\dfrac{1}{14 \ cm} -\dfrac{1}{5.8 \ cm} =- \dfrac{41}{406 \ cm} = -\dfrac{1}{f}[/tex]
Therefore;
[tex]f = \dfrac{406 \ cm}{41} \approx 9.9 \ cm[/tex]
The focal length of the mirror, f ≈ 9.9 cm
Si la rapidez del sonido en el agua es de 1450 m/s. ¿Cuánto tiempo tardará en recorrer 500 m en el fondo del lago?
Answer:
2.9
Explanation:
es 2 minutos con 9 segundos seria algo así (1450)÷(500)
1) Convert the following:
I) 65 kg into g
ii) 87570 seconds into hour
iii) 7.5 km into m
Answer:
65000g
24.325 hrs
7500m
Answer:
I) 65000 g II)24.325 hours III)7500 m
Explanation:
I) 1 kg = 1000 g
65 kg = 65 * 1000 g = 65000 g
II) 1 hour = 3600 seconds
1 second = 1/3600 hours
87570 seconds = 87570 * 1/3600 hours =24.325 hours
III) 1 km = 1000 m
7.5 km = 7.5 * 1000 m = 7500 m
Fluorometers are designed so that the path of the excitation light is at a right angle to the path of the emitted light. What is the purpose of this design
Answer: prevent excitation light from reaching the detector
Explanation:
A fluorometer refers to the device that's used in the measurement of parameters that are of visible spectrum fluorescence. They also prevent excitation light from reaching the detector.
These parameters are used in the identification of the amount and presence of molecules in a medium.
Which describes an atom that has fewer neutrons than protons and more electrons than protons?
negative compound
positive compound
positive ion
negative ion
Answer:
Negative ion
.................
Examine the equation.
-2(-x + 9) = 2(x - 9)
2x - 18 = 2x - 18
This equatior has
Answer:
same value because both sides are equal
Explanation:
equal value
Un alambre de plástico, aislante y recto mide 10 cm de longitud y tiene una densidad de carga de +150 nC/m, distribuidos de manera uniforme por toda su longitud. Se encuentra sobre una mesa horizontal. A) Encuentre la magnitud y la dirección del campo eléctrico que produce este alambre en un punto que está 8 cm directamente arriba de su punto medio. B) Si el alambre ahora se dobla para formar un círculo que se coloca aplanado sobre la mesa, calcule la magnitud y la dirección del campo eléctrico que produce en un punto que se encuentra 6 cm directamente arriba de su centro.
Answer:
English only
Explanation:
When solving problems related to Electric Fields, care must be taken about symmetries. In our particular case when we take a look to at the drawings of the attached file, we realize:
1.-By symmetry each dx associated at a, has an opposite dx with point b as reference. The respective dE ( the charge is uniform ) is the same, as the charge of the wire is positive the force and the Field on a test charge (+) located at h will be upward, therefore the components dEx will cancel each other and the Electric Field becomes E = Ey = ∫ 2×dE× cosθ
The solutions:
A) Ey = 4623 N/C
B) Ey = 19.34 N/C
E = Ey = ∫ 2×dE× cosθ
Here cosθ = h/ d ⇒ cosθ = h/√h² + x² dE = K× dQ / d²
d² = h² + x²
k = 8.9 ×10⁹ Nm²C⁻² ; dQ = λ×dx λ = 150×10⁻⁹ C h = 0.08 m
Then by substitution
Ey = 2 ∫[K× λ×dx/ (h² + x²) ] × h / √h² + x²
reordering that equation:
Ey = 2×K×λ×h ∫ dx / [√ ( h² + x² ) ]³ (2)
To solve the integral we make use of a change of variables
x = h × tanα then x² = h² ×tan²α and dx = h× sec²α dα
plugging that values in equation (2)
Ey = 2×K×λ×h ∫ h× sec²α× dα / [√ ( h² + h²tan²α)]³
Ey = 2×K×λ×h² ∫ sec²α× dα / [ h × √ (1 + tan²α)]³ 1 + tan²α = sec²α
Ey = 2×K×λ×h²× ∫ (sec²α / h³× sec³α )×dα
Ey = 2×K×λ/h × ∫ ( 1 / secα dα
Ey = 2×K×λ/h × sinα now we αneed to come back to our original variables:
as x = h × tanα tanα = x/h then x is the opposite leg in a right triangle and h the adjacent one then the hypothenuse is √ (h² + x²) then sin α = x/ √ (h² + x²)
Ey = 2×K×λ/h × x/ √ (h² + x²) |₀⁰°⁰⁵
Ey = 2×8.9×10⁹× 150×10⁻⁹× 5×10⁻²/8× 10⁻²× √ 10⁻² ( 8 + 5 ) N/C
Ey = 4623 N/C
To answer the second question again we will make use of symmetries if you look at drawing ( Figure 2 ) you see that again the components in direction of x-axis cancel each other and the components in y-axis direction will add. Then
Ey = ∫ dE× cosθ
following the same procedure we will find:
Ey = ∫ [K×λ × dl/d²] × h/ d
The importan point here is that the radius of the circle is
2×π×r = 0.01 ( the length of the wire) ⇒ r = 0.16×10⁻² m
And we need to take into account that the integration is over the circle and the length of the circle is 0.01 m or ××2×π×r. All other factors are constant. Then by substitution
Ey = [K×λ ×h× / ( √ r² + h²)³ ] × 10⁻² N/C
Ey = 8.9 × 10⁹ × 150× 10⁻⁹ × 6× 10⁻² × 10⁻² / √ 10⁻² ( 0.16 + 6)
Ey = 0.8 × 10² / 6
Ey = 19.34 N/C
by how much is the weight of body less on the moon surface than on earth surface why
Answer:
Our weight on moon is less than it would be on Earth.
Explanation:
Due to a difference of the strength of gravity on the moon. The moon's gravitation force is determined by the mass and the size of the moon. Since the moon has significantly less mass than the Earth, it will not pull objects toward itself at the strength that Earth will. This means that if you went to the moon you would weigh less, even though your mass stays the same.
An ammeter with a resistance of 5.0 ohm is connected in series with a 3.0V cell and a lamp rated at 300 mA, 3V. Calculate the current that the ammeter will measure.
plz solve this, I'll mark you as brainliest
Answer:
I = 0.2 A
Explanation:
Lamp is rated at 300 mA
I_lamp = 300 mA = 0.3 A
Voltage is; V = 3V
Thus; Resistance is given by;
R = V/I
R = 3/0.3
R = 10 ohms
Now, since the ammeter of 5 ohms is connected in series with the lamp. Thus equivalent resistance;
R_eq = 10 + 5
R_eq = 15 ohms
Ammeter current will be;
I = V/R_eq
I = 3/15
I = 0.2 A
The four laws of liquid pressure
Answer:
1-The liquid pressure is same at all points lying on the same horizontal plane in a stationary liquid.
2-The liquid pressure at a point inside the liquid is same in all directions.
3-The liquid pressure at a point inside the liquid is directly proportional to the depth of that point from the free surface of liquid.
4-The pressure of liquid at same depth is different for different liquids. It is directly proportional to density of liquid. That is, for same depth the liquid pressure is larger for liquid of larger density.
Explanation:
1. Un cable está tendido sobre dos postes colocados con una separación de 10,0 m. A la
mitad del cable esta colgado un letrero que provoca que el cable baje 50,0 cm. Si la tensión
de cada segmento del cable es de 2 000 N ¿Cuál es el peso del letrero?
1.Realice el esquema o dibujo de la situación del problema
2. Realice el Diagrama de Cuerpo Libre sobre el letrero, recuerde colocar el valor del ángulo de cada tensión.
plis s
Explanation:
Hydraulic Pressure-Control, On-Off Deluge Valve
FP-400Y-5DC
The BERMAD model 400Y-5DC is an elastomeric, hydraulic line pressure operated deluge valve, designed specifically for advanced fire protection systems and the latest industry standards. The 400Y-5DC is activated by a hydraulically operated relay valve, through which opening and closing of the valve can be controlled either with a remote hydraulic command or with a wet pilot line with closed fusible plugs. An integral pressure reducing pilot valve ensures a precise, stable, pre-set downstream water pressure. The optional valve position indicator can include a limit switch suitable for Fire & Gas monitoring systems. The 400Y-5DC is ideal for systems that combine a remote wet pilot line with a high pressure water supply.
Find the moment of inertia of a hoop (a thin-walled, hollow ring) with mass MMM and radius RRR about an axis perpendicular to the hoop's plane at an edge.
Answer:
I = sum m *r^2 where m represents the (small) individual masses and r is the distance of that mass from center of rotation
Note: sum m = M
For the hoop given all masses are at a distance RRR from the center of rotation
I = MMM * RRR^2
find the x component of a vector of 105 km/h at an angle of 25 degrees.
Answer:
Explanation:
First I converted the km/h to m/s, which is the more common unit for velocity. In m/s, 105 km/h is 29.2. Thus, to find the x component of the vector:
29.2cos25 = 26 m/s
If you want it in km/h:
105cos25 = 95 km/h
CLASS ENVIRONMENTAL SCIENCE
The____domain incorporates cultural norms that directly impact sustainable development. The___ domain focuses on the protection and preservation of natural and artificial resources
Blank 1: Blank 2:
A: social. A: public policy
B: economic. B: technological
C: sustainable. C: environmental
100 g of water are cooled and the enthalpy change is -12,540 J. What is the change in temperature of the water?
Answer:
-29.9907
Explanation:
c = Q / (mΔT)
You're looking for ΔT, so you would plug in what you already know and get C= -12540/(100 x ΔT)
then you would solve
How much heat is required to evaporate 0.15 kg of lead at 1750°C, the boiling point for lead? The heat of vaporization for lead is Lv = 871 × 103 J/kg.
Answer:
Heat required = mass× latent heat Q = 0.15 × 871 ×
The heat required to evaporate 0.15 kg of lead at 1750°C will be 130,650 J.
What is heat?The movement of energy from a hot to a cold item is characterized as heat. Heat energy flows from a hot material to a cold one.
This occurs because faster-vibrating molecules transmit their energy to slower-vibrating ones.
The given data in the problem is;
m is the mass of lead = 0.15 kg
T is the temperature = 1750°C,
The latent heat of vaporization for lead is, [tex]\rm L_V[/tex] = 871 × 10³ J/kg.
The heat is found as;
[tex]\rm Q= m \times L_V \\\\ \rm Q= 0.15 \times 871 \times 10^3 \\\\ Q=130,650 \ J[/tex]
Hence the heat required to evaporate 0.15 kg of lead at 1750°C will be 130,650 J.
To learn more about the heat refer to the link;
brainly.com/question/1429452
Suppose that you are standing on a train accelerating at 0.20g (where g is the acceleration due to gravity). What minimum coefficient of static friction must exist between your feet and the floor if you are not to slide
Answer:
0.2
Explanation:
The given parameters are;
The acceleration of the train, a = 0.2·g
The mass of the person standing on the train = m
Let μ represent the coefficient of static friction, we have;
The force acting on the person, F = m × a = m × 0.2·g
The force of friction acting between the feet and the floor, [tex]F_f[/tex] = m·g·μ
For the person not to slide we have;
The force acting on the person = The force of friction acting between the feet and the floor
F = [tex]F_f[/tex]
∴ m × 0.2·g = m·g·μ
From which we get;
0.2 = μ
The coefficient of static friction that must exist between the feet and the floor if the person is not to slide, μ = 0.2.
18.How much momentum will a dump-bell of mass 10 kg transfer to the floor if it falls from a height.of 80 cm ? Take its downward acceleration to be 10 m s-2
Such asSuch ToSuch aSuch as طHow do I send the answer to the question?OkI don't know how to use this program
Answer:
MOMENTUM = 40kg ms-¹
hope it helps
have a nice day
Answer all these questions
What type of waves can only travel through a medium?
What is pitch?
What is the relationship between amplitude and volume?
How does the type of medium affect a sound wave?
Describe the relationship between frequency and wavelength.
Answer:
mechanical waves,
.
the quality of a sound governed by the rate of vibrations producing it; the degree of highness or lowness of a tone.
.
If the amplitude increases the volume increases and vice versa.
.
The type of medium affects a sound wave as sound travels with the help of the vibration in particles.
.
The higher the frequency, the shorter the wavelength.
Explanation:
Answer:
1 . Soundwave
2. pitch are sounds that are high or low corresponding and according to a certain frequency measured in Hertz
3. volume is the increase in sound or decrease in sound how loud or soft something is while amplitude is strength of sound
4. frequency is measured in Hertz one wave per second and wavelength is distance between corresponding points of two recurring and consecutive sound waves
As the motor speeds up, the value of current decreases because of A. Friction loss B. Increase in resistance C. Increase in back emf D. All mentioned above
Answer:
C. Increase in back emf
Explanation:
As the current through the field winding decreases the field strength also decreases and the back-emf is reduced, as a result the motor speeds up.
When the motor begins to speed-up, an additional back EMF is generated due to induction which reduces armature current. This also results in reduced strength of the field flux. The back emf generated is not enough to reduce the armature current which could stop the acceleration of the motor and the motor further accelerates.
A mass that weighs 8 lb stretches a spring 24 in. The system is acted on by an external force of 4 sin 4t lb. If the mass is pulled down 6 in. and then released, determine the position of the mass at any time. Determine the first four times at which the velocity of the mass is zero
Answer:
[tex]t = \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}, \frac{3 \pi}{4}[/tex]
Explanation:
The equation of force is
F = 4 sin 4 t
Compare with the standard equation
f = A sin wt
where, w is the angular frequency and A is the amplitude.
Now
w = 4 rad/s
Let the time period is T.
the relation for the time period is
[tex]T = \frac{2\pi}{w}\\\\T = \frac{2 \pi}{4}\\\\T = \frac{\pi}{2}[/tex]
the time period is defined as the time taken by the body to complete one oscillation.
So, the velocity is zero at the extreme points where the object is at time, T/4 and its odd T/2, 3T/4, 3T/2, etc.
So, the velocity is zero at time
[tex]t = \frac{\pi}{8}, \frac{\pi}{4}, \frac{3\pi}{8}, \frac{3 \pi}{4}[/tex]
The chart shows the speed at which light travels through different media.
In which medium would light have the longest wavelength?
- Water
- Air
- Glass
- Diamond
Answer:
Air.
Explanation:
To know which option is correct, let us consider the relationship between velocity and the wavelength of a wave. This is illustrated below:
Velocity, wavelength and frequency are related by the following equation:
Velocity = wavelength × frequency
v = λf
From the equation above, we can see clearly that the velocity is directly proportional to the wavelength.
This means that an increase in the wavelength will lead to an increase in the velocity and also, a decrease in the wavelength will lead to a decrease in the velocity.
Now, considering the table given in the question above, we can see that the wave has a higher speed in air. This simply means that the wave will also have a higher wavelength in air.
Thus, the correct answer to the question is: air
how to answer thiss helppp
Answer:
Look at work
Explanation:
Your given the mass of planet M and radius as well as second mass.
Use universal gravitation law to find force of gravity
Fg= Gm1m2/r^2
Plug in givens
Fg= 553.6 N
Use newtons second law
Fg= ma
553.6N=5a
solve for a= 110.72m/s
Weight is 553.6N
what is the closest to the order of magnitude of the energy rquired to split a nucleus in to its individual protons and neutrons
Answer:
More than two million electron volts.
Explanation:
More than two million electron volts energy are needed to break or split a deuteron into a proton and a neutron. Nuclear binding energy is the type of energy that is required to split an atom's nucleus into protons and neutrons. The deuteron is an isotope of hydrogen that is composed of a proton and a neutron and it is a stable particle. Very huge amount of energy is needed for the splitting of nucleus due to the presence of heavy particles i.e. proton and neutron.
A car is moving at 30km/h. What is its speed in m/s? Give your answer to 2 significant figures.
Explanation is in the attachment
hope it is helpful to you
Which part of this model represents a layer made of liquid rock that produces
a magnetic field?
A. B
B. A
C. D
D. C
Answer: C- the outer core
Explanation: The outer core is a thick layer of molten rock that encircles the inner core.
suppose the pilot starting again from rest opens the throttle part.way at constant acceleration the airboat then covers a distance of 60.0m in 10.0s find the net force action on the boat
Answer:
Acceleration is 1.2 m/s^2.
Explanation:
initial velocity, u = 0
distance, d = 60 m
time, t = 10 s
Let the acceleration is a.
use second equation of motion
[tex]s= u t +0.5 at^2\\\\60 = 0 + 0.5 \times a \times 10\times 10\\\\a = 1.2 m/s^2[/tex]
Now according to the Newton's second law
Force = mass x acceleration
Let the mass is m.
F = m x 1.2 = 1.2 m Newton
Please help me with this!!!
Answer:
Its all about figuring out what numbers you times by
Explanation:
soooooooooo just x the numbers until you get it right, and i'm guessing your in a school soooo ask your teacher aswell :)
The large reservoir of comet nuclei far beyond Pluto, from which we believe new long-period comets come into the inner solar system, is called:
Answer:
Oort cloud
Explanation:
The large reservoir of comet nuclei far beyond Pluto, from which we believe new long-period comets come into the inner solar system, is called Oort cloud.
The comets hich have the large periods that means more than 200 years to orbit the Sun generaly comes from Oort cloud hich is also knon as the cometary cloud.
A stationary body explodes into four identical fragments such that three of them fly off mutually perpendicular to each other, each with same KE, E 0 . The energy of explosion will be Aa
Answer:
6Eo
Explanation: