Explanation:
8. Real and inverted
9. Concave mirror
How many atoms are in 2Mg3(PO4)2?
Answer:
13 atoms
Explanation:
Look at the subscripts.
“Mg₃” means that there are 3 magnesium atoms; “PO₄” means that there is 1 phosphorus atom and 4 oxygen atoms. But note that the PO₄ group has a subscript too: 2. This multiplies the atom count by 2, so you have 2 phosphorus atoms and 8 oxygen atoms.
3 + 2 + 8 = 13
(hope this helps can i plz have brainlist :D hehe)
There are total 26 atoms in 2Mg₃(PO₄)₂ compound. in one Mg₃(PO₄)₂, there are 13 atoms. Therefore, in 2 Mg₃(PO₄)₂ units, there are 26 atoms in total.
What is chemical formula ?A chemical formula is used identify a compound and to indicate chemical composition. The molecular formula of a compound is written based on the chemical symbol of each constituent atoms and their numbers.
The number of the atoms of each elements are represented as subscripts for each elemental symbol. In the given compound Mg₃(PO₄)₂, one unit of the compound contain 3 Mg atoms, and 2 PO₄ units means 2 P and 8 oxygen atoms. Hence there are 13 atoms in one unit.
There are 2 such units of this compound. Therefore, the total number of atoms present in 2 units Mg₃(PO₄)₂ compound is 13×2 =26.
Find more on chemical formulas:
https://brainly.com/question/29031056
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.
Humans sleep in cycles, usually two or three cycles per night. There is a point in each cycle when waking up will leave the sleeper feeling the most rested and refreshed.
After learning about this, a computer programmer designed a new smartphone alarm clock. This new alarm clock uses sensors in the smartphone to detect the sleeper’s motion and determine when the sleeper has reached the best point in the sleep cycle at which to wake up. The app can be downloaded onto any smartphone. Most users who download this app find that it does not help them wake up feeling more refreshed, but they are willing to try improved products in the future.
Which criterion did this sleep cycle alarm clock fail to meet?
It did not solve the problem.
It was not cost effective enough.
It was not readily available.
It was not safe for most users.
Answer:
A
Explanation:
It did not solve the problem.
Study of the ___________
effect helped convince
scientists that light could behave as both a particle and a wave.
Answer: Photoelectric effect
Explanation:
A tourist follows a passage that takes her 160 m west, then 180.m at an angle of 45.0∘ south of east, and finally 250 m at an angle 35.0∘ north of east. The total journey takes 12 minutes. (4)
a. Calculate the magnitude of her displacement from her original position.
b. She measures the distance she has walked to a precision of 5%. She times her total journey to ±20 s. (4)
(i) What is her average speed?
(ii) What is the absolute uncertainty on her absolute speed?
Answer:
a) R = 172.82 m, 5.3 north of east b) v = (0.24 ± 0.01) m / s
Explanation:
a) the displacement is a vector, so the easiest method to lock is looking for each component
let's start decomposing the vectors
x₁ = - 160 m
second shift
angle 45 south of east
cos (-45) = x₂ / d₂
sin (-45) = y₂ / d₂
x₂ = d₂ cos 45
y₂ = -d₂ sin 45
x₂ = 180 cos 45 = 127.28 m
y₂ = -180 sin 45 = - 127.28 m
third shift
cos 35 = x₃ / d₃
sin 35 = y₃ / d₃
x₃ = d₃ cos 35
y₃ = d₃ sin 35
x₃ = 250 cos 35 = 204.79 m
y₃ = 250 sin 35 = 143.39 m ₃
X axis
x_total = x₁ + x₂ + x₃
x_total = -160 +127.28 +204.79
x_total = 172.07 m
Y axis
y_total = y₁ + y₂ + y₃
y_total = 0 - 127.28 + 143.39
y_total = 16.11 m
to compose the displacement we use the Pythagorean theorem
R = [tex]\sqrt{x^2 +y^2}[/tex]
R = [tex]\sqrt{172.07^2 + 16.11^2 }[/tex]
R = 172.82 m
in angle is
tan θ = y_total / x_total
ten θ = 16.11 / 172.07 = 0.0936
θ = tan⁻¹ 0.0936
θ = 5.3
angle is 5.3 north of east
b) the error in the distance is 5%,
e% = ΔR/R 100
ΔR = e% R / 100
ΔR = 5 172.82 / 100
ΔR = 8.6 m
the time error Dt = 20 s
We calculate the speed and this we calculate the error
v = R / t
v = 172.82 / 12 60
v = 0.240027 m / s
the error in this magnitude is
Δv = [tex]\frac{dv}{dR} \ \Delta R + \frac{dv}{dt} \ \Delta t[/tex]
Δv = [tex]\frac{1}{t} \ \Delta R + \frac{R}{t^2 } \ \Delta t[/tex]
Δv = [tex]\frac{ 8.6}{720} + \frac{172.82 \ 20}{720^2 }[/tex]
Δv = 0.013 m / s
the measurement result is
v = (0.24 ± 0.01) m / s
3. What is the function of a fuse in an electrical circuit
Answer:
The fuse breaks the circuit if a fault in an appliance causes too much current to flow. This protects the wiring and the appliance if something goes wrong. The fuse contains a piece of wire that melts easily.
Explanation:
MARK AS BRAINLIST!!
Can somebody answer this science question NO LINKS !!!!
Answer:
position 1
Explanation:
in position 2 and three it would have less energy cause there is less force being exerted to give it that push, but at the end position and the first position there is going to be more force and energy behind the ball.
Based on the model, which three factors might cause this change in the apparent movements of the stars? A. Earth's rotation on its axis B. Earth's revolution around the Sun C. The tilt of Earth's axis D. Earth's changing distance from the Sun
Answer:
I think it's A C and D sry if I'm wrong UwU
Item 3 A manufacturer makes lightbulbs and claims that their reliability is 98 percent. Reliability is defined to be the proportion of nondefective items that are produced over the long term. If the company's claim is correct, what is the expected number of nondefective lightbulbs in a random sample of 1,000 bulbs?
Answer:
980 is the expected number of nondefective lightbulbs in a random sampling of 1,000 bulbs
Explanation:
If the company claims is right, this is the task that should be done
Lightbulbs = 1,000 * 0.98 = 980
Therefore, 980 working bulbs is expected out of a sample of 1,000 lightbulbs
hi please answer and show your work
Answer:
[tex]\huge\boxed{\sf P.E. = 240\ MJ}[/tex]
[tex]\huge\boxed{\sf K.E. = 19.6\ MJ}[/tex]
Explanation:
Given:
Mass = m = 200,000 kg
Vertical Distance = h = 120 m
Speed = v = 14 m/s
Acceleration due to gravity = g = 10 m/s²
Required:
1) Gravitational Potential Energy = P.E = ?
2) Kinetic Energy = K.E. = ?
Formula:
1) P.E. = mgh
2) K.E. = [tex]\displaystyle \frac{1}{2} mv^2[/tex]
Solution:
1) P.E. = (200,000)(10)(120)
P.E. = 240,000,000 Joules
P.E. = 240 Mega Joules
P.E. = 240 MJ
2) K.E. = 1/2 (200000)(14)^2
K.E. = (100000)(196)
K.E. = 19,600,000 Joules
K.E. = 19.6 MJ
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807Three 44-ohm resistors are connected in parallel with an ideal 12-volt battery. What is the equivalent resistance of the circuit?
Answer:
Explanation:
1/Rtotal = 1/r1 +1/r2 +1/r3
1/Rtotal = 1/44 + 1/44 + 1/44
1/Rtotal = 3 /44
1/Rtotal = 0.0681818182
1/0.0681818182 = Rtotal
14.66666666666666666 = Rtotal
14 [tex]\frac{2}{3}[/tex] ohms = Rtotal
How are electrical charges similar to magnets?
Answer:
The two types of forces are related; a moving magnet can make electrical charges move, cause an electric current, and in turn cause magnetism. ... Objects that have the same charge, both positive or both negative, repel each other, and those with opposite charges attract each other.
Explanation:
Two planes approach each other head on. Each has a speed of 721km/h and they spot each other when they are initially 14.7km apart. How many seconds (s) do the pilots have to take evasive action?
Answer:
The time the pilots have to take evasive action is approximately 36.699 seconds
Explanation:
The direction of the planes = Towards each other
The speed of each plane, v₁, v₂ = 721 km/h
The initial distance between the two planes, d = 14.7 km
The relative velocity of the two planes, v = v₁ + v₂
v = 721 km/h + 721 km/h = 1,442 km/h
The time it will take the planes to meet, t = d/v
∴ t = 14.7 km/(1,442 km/h) = (21/2,060) h × 60 min/hr × 60 s/min ≈ 36.699 s
The time it will take the planes to meet = The time the pilots have to take evasive action, t ≈ 36.699 seconds.
You've probably seen how the surface of a tire can partially melt and leave a mark on the road when a car's brakes are applied really hard. Explain why the surface of the tire melts.
Answer:
tire marks are due to the increase in thermal energy
Explanation:
When a tire is spinning at a given speed when the brakes are applied hard, the friction between the tire's particulate and the ground surface is high enough that some tire particles are transferred to the ground.
This is reflected in the heat transfer from the tire to the ground.
Consequently, tire marks are due to the increase in thermal energy and the change in the friction force of the tire.
Answer:
Going super fast and stopping abruptly causes friction which causes heat thus it melts the surface of the tire.
Explanation:
This is example answer for edmentum :)
Check out the list of scientific names. These names all represent animals. These are all annals but they cannot reproduce fertile offspring with each other. What conclusion can be drawn from the past statement?
Answer:
None of the animals are from the same species
Explanation:
The exact question is as follows :
Given -
Felis catus
Sylvilagus audubonii
Parus inornatus
Euarctos americanus
Check out the list of scientific names. These names all represent animals. These are all animals but they cannot reproduce to produce fertile offspring with each other.
To find - What conclusion can be drawn from the past statement?
Solution -
The conclusion we can made from past statement is that - None of the animals are from the same species
Reason -
When two members of the same species reproduce, they produce fertile offspring.
According to the scientific names of the animals, there are different genus and species names.
An unknown material has a mass of 3.5 g and a volume of
5.5 cm3 What is the density of the material? Round to the nearest tenth.
Explanation:
Density=mass/volume
density= 3.5 g ÷ 5.5cm
density=0.63
what are the advantages of having a roof with a lower thermal conductivity
Answer:
A thick layer of material with a low thermal conductivity reduces the rate of heat transfer from the ceiling into the roof space.
How would mass determine if an egg will crack or not and why?
How much work is done on a small car if a 3150 N force is exerted to move it 75.5 m to the side of the road
Answer:
Explanation:
Work = Force times displacement. Therefore,
W = 3150(75.5) so
W = 238000 N*m
¿Con que fuerza se atraen dos masas de 50kg y 700 kg que están separadas por una distancia de 5 cm?
Answer:
F = 9.338 10⁻⁴ N
Explanation:
For this exercise let's use the law of universal gravitation
F = [tex]G \frac{m_1m_2}{r^2}[/tex]
let's reduce the magnitudes to the SI system
r = 5 cm (1 m / 100cm) = 0.05 m
let's calculate
F = 6.67 10⁻¹¹ 50 700 / 0.05²
F = 9.338 10⁻⁴ N
the direction of the force is in the direction between the particles
A tank has the shape of an inverted circular cone with height 16m and base radius 3m. The tank is filled with water to a height of 9m. Find the work required to empty the tank by pumping all of the water over the top of the tank. Use the fact that acceleration due to gravity is 9.8 m/sec2 and the density of water is 1000kg/m3. Round your answer to the nearest kilojoule.
Answer:
[tex]W=17085KJ[/tex]
Explanation:
From the question we are told that:
Height [tex]H=16m[/tex]
Radius [tex]R=3[/tex]
Height of water [tex]H_w=9m[/tex]
Gravity [tex]g=9.8m/s[/tex]
Density of water [tex]\rho=1000kg/m^3[/tex]
Generally the equation for Volume of water is mathematically given by
[tex]dv=\pi*r^2dy[/tex]
[tex]dv=\frac{\piR^2}{H^2}(H-y)^2dy[/tex]
Where
y is a random height taken to define dv
Generally the equation for Work done to pump water is mathematically given by
[tex]dw=(pdv)g (H-y)[/tex]
Substituting dv
[tex]dw=(p(=\frac{\piR^2}{H^2}(H-y)^2dy))g (H-y)[/tex]
[tex]dw=\frac{\rho*g*R^2}{H^2}(H-y)^3dy[/tex]
Therefore
[tex]W=\int dw[/tex]
[tex]W=\int(\frac{\rho*g*R^2}{H^2}(H-y)^3)dy[/tex]
[tex]W=\rho*g*R^2}{H^2}\int((H-y)^3)dy)[/tex]
[tex]W=\frac{1000*9.8*3.142*3^2}{9^2}[((9-y)^3)}^9_0[/tex]
[tex]W=3420.84*0.25[2401-65536][/tex]
[tex]W=17084965.5J[/tex]
[tex]W=17085KJ[/tex]
'
'
David runs 100 m in a time of 9.80 s. Calculate his average speed. State the unit.
Answer:
His average speed is 980 units
PLS PLS HELP FOR BRAINLIEST!!!!!!!!!!!!
Option A: The air molecule moves from the girl's mouth to the ear of her friend
A wave has frequency of 50 Hz and a wavelength of 10 m. What is the speed?
Answer:
v=500 m/s
Solution:v=(10m)(50/s)
Based on which principle does a circuit work?
Answer:
Under normal conditions – closed circuit – these contacts are touching each other, allowing the flow of electric current. These moving contacts are held together thanks to mechanical pressure exerted by another mechanism – a spring or compressed air
Describe different types of motion with examples. (4)
(b) difference between scalar and vector. (2)
(c) A car has a velocity of 10 ms-1
. It accelerates at 0.2 ms-2
for half minute. Find the distance
Answer:
a)
there r two types of motion, uniform and non-uniform
uniform means equal distance travelled at equal intervals of time
and non-uniform is exactly the opposite.
b)
quantities which can be represented by magnitude along r called scalar quantities such as speed.
quantities which need magnitude along with direction r called vector quantities such as velocity.
c)
velocity=10m/s
acceleration = u-v/s i.e initial final velocity - initial velocity upon time
acceleration= 0.2m/s sq
time= 30s
10 = displacement/time
10 = x/30
10 = 300
Answer is 300 meters - distance/displacement.
Which is a valid ionic compound?
sodide chlorine
sodium chlorine
sodium chloride
sodide chloride
Answer:
sodium chloride
Explanation:
Sodium chloride is an ionic compound. The ions of the sodium chloride compound is sodium ion and chloride ion. The sodium ion is cation while the chloride ion is an anion. Sodium chloride is a very stable compound because of the mutual attraction of oppositely charged ions.
a wave has a frequency of 10Hz and a wavelength of 30 m. What's its velocity?
1. Nombrar mediante ITEMS las características que tiene el musculo de pescado y como se diferencian del musculo animal terrestre.
Answer:
Similitudes y diferencias entre los músculos de los peces y los de los animales terrestres.
Explicación:
Los músculos de los peces se diferencian del músculo de los animales terrestres porque los peces tienen músculos rojos, rosados y blancos. También tienen tejido muscular de pescado que se compone de músculo estriado al igual que el músculo de los animales terrestres. La mayor parte del tejido muscular de los peces es de color blanco, pero muchos peces también tienen una cierta cantidad de tejido oscuro de color marrón o rojizo. El músculo oscuro se encuentra justo debajo de la piel a lo largo del costado del cuerpo.
Under what condition do the values of gravitational
force, and gravitational constant become same/
equal
Answer:
values of gravitational force and gravitational constant become same or equal when product of masses involved equals the square of distance between them
Explanation:
Magnitud del momento de una fuerza respecto a un punto cuando la línea de acción de la fuerza pasa por dicho punto.
Answer:
τ = 0
Explanation:
The moment of a force is defined by
τ = F x r
where bold indicates vectors.
We can write this equation in module form
τ = F r sin θ
the amount without ea r is called the breaststroke and is the distance perpendicular to the pivot point.
The line of action of the force passes through the turning point whereby
r = 0,
Consequently the moment is also zero
τ = 0