Answer: 0.3m
Explanation:
Given the following :
Speed of radio wave(V) = 3 × 10^8 m/s
If 1M = 10^6
Frequency(F) = 90MHz = 90 × 10^6
Wavelength (λ) =?
Speed of wave (V) = frequency(F) × wavelength(λ)
V = fλ
(3 × 10^8) = (90 × 10^6) × λ
λ = (90 × 10^6) / (3 × 10^8)
λ = 30 × 10^(6 - 8)
λ = 30 × 10^-2
λ = 0.3m
Njoki planted trees at intervals of 22m apart on the diagonal of a rectangular plot of land that measures 48m by 20m . How many trees did he plant
Answer:
The number of tree is 2Explanation:
the diagonal of the rectangular plot of land can be found using Pythagoras theorem (the diagonal is the hypotenuse)
Given
length of land x= 48m
width of land y= 20m
digonal z= ?
[tex]z^2= x^2+y^2\\\\z=\sqrt{ x^2+y^2} \\[/tex]
substituting the values of x and y into the equation we can solve for z
[tex]z=\sqrt{ 48^2+20^2} \\\\z=\sqrt{ 2304+400} \\z=\sqrt{ 2704} \\z=52m\\[/tex]
The diagonal is 52m
Hence since the interval = 22m the number if treee is
[tex]\frac{52}{22} = 2.36\\[/tex]
The number of trees must be whole numbers , the number of tree is 2
*
A light year is
1 Point
O 365 days
O The distance light travels in a year
O The distance from Earth to Proxima Centauri
Helppp now is my final exammmm pleaseeee
Answer:
2.The Distance Light Travels In A Year
Explanation:
A Light Year Is Nothing But The Distance That The Light Travels In Onw Year
Answer:
Shown from explanation.
Explanation:
Light year is the distance light travels in one year and you can calculate that.
Light travels 3× 10^8m in 1 second; so you calculate the number of seconds in 365days and multiply by 3× 10^8m.
Light year was a unit of measure derived by man for expressing planetary distances due to their so huge distance which goes beyond our scale of measure.
What are some advantages
and disadvantages to using
superconductors as electric
transmission lines
Answer:
Insulators show very high resistance to electricity. Conductors like copper show some resistance. Another class of materials show no resistance at all when cooled to very low temperatures, cooler than the coolest deep freezer. Called superconductors, they were discovered in 1911.
Explanation: i looked it up
Un movil pasa por el punto A en direccion hacia B (350cm más adelante) y, luego, sigue hasta el punto C. Sabiendo que pasa por B a las 11:42:38 y por C a las 11:43:16, completando un tiempo total de recorrido de 3min 47s, calule la distancia entre B y C y a la hora a la que paso por el punto A.
Explanation:
PRIMERO HACES EL RECUENTO DEL TIEMPO Y LO CONVIERTES EN
SEGUNDOS Y ENTONCES
t = 227 s [tex]t_{AB}[/tex] = 227 S - 38 s = 189 s
[tex]t_{BC}[/tex] = 38 s
LUEGO USANDO LA ECUACIÓN DE GALILEO GALILEI SSUPONIENDO
QUE EL MOVIL VIAJA A VELOCIDAD CONSTANTE
v = 3.50 m/189 s = 0.0185 m/s
PARA LA DISTANCIA NTRE B Y C
[tex]x_{BC}[/tex] = 0.0185 m/S( 38 s) = 0.703 m
LA HORA EN QUE EL MOVIL PASA POR A ES
11:43:15 - 38 s - 189 s = 11:39:29
this principle is useful in solar cooker but can be harmful on earth?
Answer:
Green House Effect
Explanation:
Green House Effect is the principle used in solar cookers but it can be really harmful for the Earth producing some green house gases.
Prove that the acceleration due to gravity is independent to
the mass of the falling body
Answer:
The force of gravity on an object increases with its mass; thus, the acceleration of gravity is constant.
Explanation:
one can prove this by plugging in values to Newton's 2nd law equation
F = ma, or by using the formula to calculate the force of gravity.
Force of Gravity = GMm/r^2
with G being the gravitational constant, M the mass of the earth, m the mass of the falling body, and r the distance from the earth's center.
Force of Gravity can be written as mg, with g being the acceleration due to gravity.
As we can see, m cancels on both sides, leaving
g = GM/r^2
Generally in physics problems, r will be treated as constant to achieve
g = 9.8m/s^2
The diagram below shows a 5.0-kilogram bucket of water being swung in a horizontal circle of 0.70-meter radius
at a constant speed of 2.0 meters per second.
5.0-kg Bucket
0.70 m
The magnitude of the centripetal force on the bucket of water is approximately
1) 5.7 N
2) 14 N
3) 29 N
4) 200 N
Answer:
F = 29 N
Explanation:
We have,
Mass of the bucket of water is 5 kg
Radius of a horizontal circle is 0.7 m
Speed of the circle is 2 m/s
It is required to find the magnitude of centripetal force on the bucket of water. The formula used to find the magnitude of centripetal force is given by :
[tex]F=\dfrac{mv^2}{r}\\\\F=\dfrac{5\times (2)^2}{0.7}\\\\F=28.57\ N[/tex]
or
F = 29 N
So, the centripetal force on the bucket of water is 29 N.
The magnitude of the centripetal force on the bucket of water is approximately 29 N
Definition of centripetal forceCentripetal force is the force that acts to keep an object moving in a circular motion. It is expressed mathematically as:
F = mv² / r
With the above formula, we can obtain the centripetal force acting on the bucket.
How to determine centripetal force•Mass (m) = 5 Kg
•Radius (R) = 0.7 m
•Velocity (v) = 2 m/s
•Centripetal force (F) =?
F = mv² / r
F = (5 × 2²) / 0.7
F = (5 × 4) / 0.7
F = 20 / 0.7
F = 29 N
Learn more about centripetal force:
https://brainly.com/question/10596517
When a rocket accelerates through space is there work done?
Rhodes research indicates that people are generally accurate in guessing the ages of unfamiliar persons based on their faces. This research has important implications for
The available options are:
A. bartenders serving alcohol
B. students identifying their professors.
C. Doctors diagnosing cases of schizophrenia.
D. eyewitnesses identifying suspects from a lineup.
Answer:
A. bartenders serving alcohol
Explanation:
This is because of the underage rule concerning sale of alcohol. Thus, there are occasional period in which underage person or a minor will want to buy alcohol, and without necessarily asking for the birth certificate or ID card that contains Age information, it is therefore, necessary for bartenders to be able to tell the age of their unfamiliar customers, by mere looking at them, so as not to sell to a minor.
Hemce, Rhodes research in guessing the age of unfamiliar person has important implications for BARTENDERS SERVING ALCOHOL, because it will guide them to determine Underage or Minor, that want to buy alcohol from them.
A 50 - N x m torque acts on a wheel with a moment of inertia 150 kg x m² . If the wheel starts from rest , how long will it take the wheel to make one revolution ?
Answer:
t = 6.17 s
Explanation:
For a 1 revolution movement, [tex]\triangle \theta = 2\pi[/tex]
Torque, [tex]\tau = 50 Nm[/tex]
Moment of Inertia, [tex]I = 150 kg m^2[/tex]
If the wheel starts from rest, [tex]w_{0} = 0 rad/s[/tex]
The angular displacement of the wheel can be given by the formula:
[tex]\triangle \theta = \omega_0 t + 0.5 \alpha t^2[/tex]................(1)
Where [tex]\alpha[/tex] is the angular acceleration
[tex]\tau = I \alpha\\\alpha = \frac{\tau}{I} \\\alpha = 50/150\\\alpha = 0.33 rad/s^2[/tex]
To get t, put all necessary parameters into equation (1)
[tex]2\pi = 0(t) + 0.5(0.33)t^2\\2\pi =0.5(0.33)t^2\\t^2 = \frac{4 \pi}{0.33} \\t^2 = 38.08\\t = 6.17 s[/tex]
what is an atomic nucleus?
It is basically a very tiny region centering around protons and neutrons in the center of a atom
the weight of a body of certain mass become zero in space.why?
Answer:
There is no force in space.
Explanation:
Weight is the gravitational force acting on the mass as in space there is no gravity so weight appeares as zero
Answer:
It is because of gravity that your weight of a certain mass becomes zero in space.
Explanation:
Please explain how you got the answer :(
Answer:
36.5 kJ
Explanation:
Energy by machine = energy to machine × efficiency
E = 52.1 kJ × 0.70
E = 36.5 kJ
which of the following terms describes a machine that converts heat into work?
A. Entropy pump
B. Heat engine
C. Heat pump
D. Entropy engine
Answer: A
Heat engine
Explanation: just took the test
What is the symbol for Pressure ? Help
Answer:
The answer is Pascal or Pa.
Answer:
Pa or small p
Explanation:
Force over Area. The SI unit is Pascal
A 31.7 kg kid, initially at rest, slides
down a frictionless water slide at 53.2º.
How fast is she moving 3.45 s later?
Answer:
34.55m/s
Explanation:
Now from Newton's law of motion;
V= U+ a×t
V- final velocity
U- initial velocity = 0m/s
a- acceleration
t- time
Note that a = g/cos53.2°
Now g is acceleration of free fall due to gravity
This is a vertical acceleration since the course of motion is along a plane inclined at 53.2° to the height of the pool.
Also from trigonometry identity
cos 53.2°= vertical component a/ acceleration ( cos a = adjacent/hypothenus)
If we assume g = 9.8m/S2 { a generally given value}
Substituting t = 3.45s as the time of consideration, we have;
V = 0 + (9.8/cos53.2°)×3.45
= -34.55m/s
Note the -ve sign is just telling us this velocity is causing the object to move down.
Hence V = 34.55m/s
Answer:
27.07 m/s
Explanation:
this is the right answer
A rocket is launched from atop a 101 foot cliff with an initial velocity of 116 ft/s.
\a. Substitute the values into the vertical motion formula h(t) = -16t2 + vt + h0 . Let h(t) = 0
b. How long will the rocket take to hit the ground after it is launched? Round to the nearest tenth of a second.
Answer:
A. 16t2 -116t -101=0 B. 8.0s
Explanation:
Known parameters from the question:
Height of Cliff,h0 = 101ft
Velocity of rocket ,v= 116ft/s.
1.Substituting the above to the above formula we have;
h(t) = -16t2 + vt + h0
Since h(t) =0, it means the rocket is falling towards the ground, when it gets to the ground when it's at rest the height h(t) = 0m
{Note the rocket is launched from the height of the Cliff so that would be the initial height of the rocket,h0}
2.Substituting into h(t) = -16t2 + vt + h0
We have;
0 = -16t2 + 116t + 101=> 16t2 -116t -101=0
Using formula method for solving quadratic equation we have;
t = -(-116)+_√[(-116)^2 -( 4× 16 ×-101]/ (2× 16)
t = [116 +_(141.1382)]/32
t = (116 -141.1382)/32 or (116 +141.1382)/32
-0.786s or 8.036s
-0.8s or 8.0s to the nearest tenth.
Now time cannot be negative in real life situation hence the time is 8.0s
Note : the general equation of a quadratic equation with variable t is given below;
at2 + bt + c=0
Formula method for quadratic equation is :
t =( -b+_√[(b^2 -( 4× a×c)] ) / (2× a)
8. Simple machines make a job easier to perform by
a. decreasing the amount of work
b. decreasing the amount of friction
c. decreasing the amount of force and/or changing the direction of force
d. only lower the amount of force
Answer:
C
Explanation:
One of the earliest forms of load-bearing construction is the ____ method of construction.
Answer:
the materials most often used to construct load bearing walls in large building are concrete ,block or brick . load bearing walls are one of the earliest forms of construction
Explain the following behaviour of molecules water rises up in a harrow tubes but mercury which is also a liquid falls in a narrow tubes to level below the outside surface
Answer: find the answer in the explanation
Explanation:
The capillarity of water molecules is different from the mercury molecules.
What is capillarity ?
This is the tendency of a liquid substance to rise in a capillary tube.
Molecules water rises up in a harrow tubes because of the force of adhesion between the water molecules and the tube molecules is greater than the force of cohesion between the water molecules. This helps water to wet the tube and rise. While mercury which is also a liquid falls in a narrow tubes to level below the outside surface because the force of cohesion between the mercury molecules is greater than the force of adhesion between the mercury molecules and the tube molecules. Mercury does not wet.
A wave has an amplitude of 2 cm. What is its energy (KW)?
Answer:
1.962 × 10⁻³ kW
Explanation:
The energy of a wave of a wave, such as an ocean wave, in regions of considerable water depth given its amplitude in a meter of crest and surface unit is given by the relation;
[tex]E = \dfrac{\rho \times g \times A^2}{2}[/tex]
Where:
ρ = Density of water = 1000 kg/m³
g = Acceleration due to gravity = 9.81 m/s²
A = Wave amplitude = 2 cm = 0.02 m
We therefore have;
[tex]E = \dfrac{1000 \times 9.81 \times (0.02)^2}{2} = 1.962 \ \dfrac{m^2 \cdot kg}{s^2} = 1.962 \ J[/tex]
The energy is power is the energy per second which is gives;
P = E /second = 1.962 J/s = 1.962 W = 1.962 × 10⁻³ kW.
In a hydroelectric power station, how much potential energy is lost by 100tonnes of water flowing down through the pipes, falling a vertical distance of 200metres? [1tonne=1000kg.]
Answer:
196000000 J
Explanation:
Potential Energy: This can be defined as the energy of a body due to its position in the gravitational field.
From the question,
P.E = mgh.................. Equation 1
Where P.E = potential Energy, m = mass of the water, h = height, g = acceleration due to gravity.
Given: m = 100 tonnes = (100×1000) = 100000 kg, h = 200 m
Constant: g = 9.8 m/s²
Substitute into equation 1
P.E = 100000(200)(9.8)
P.E = 196000000 J.
Note: When a object falls through a height he losses its potential energy.
Hence the potential energy lost = 196000000 J = 196 MJ.
Salt is dissolved in a flask of tap water . Distilling the mixture causes the salt to separate from the water. Which type of energy is required to begin the distilling process
In some creatures, bioluminescence transforms
energy
energy into
OA) heat; light
OB) light; heat
OC) chemical potential; light
OD) light; chemical potential
Answer:
Hey!
Your answer would be option B. Light; heat...
Explanation:
In bioluminescent organisms, the energy is transformed int light energy and less then 20% of the total energy is put into Thermal Radiation!
HOPE THIS HELPS!!
explain why atmospheric pressure decreases towards higher altitudes
Answer:
At higher elevations, there are fewer air molecules above a given surface than a similar surface at lower levels. ... Since most of the atmosphere's molecules are held close to the earth's surface by the force of gravity, air pressure decreases rapidly at first, then more slowly at higher levels.
Explanation:
happy to help:)
Please help
Right answers please
Will mark brainliest
Answer:
a. 45 N. / b. 0.08 m/s^2. / c. 102 N
F = ma
F = 15(3)
F = 45 newtons
F/m = a
20/250 = a
0.08 m/s^2 = a
R = ma
R =1.5(68)
102 N
plzzzzzzz help me quick
Explanation:
in the first thing we are allowing bacteria to grow
in the second one we are killing it
why is no one helping?
Answer:
First one is hyperopia, second is myopia
Explanation:
Hyperopia is when the image is formed behind the retina.
Myopia is when images are formed infront of the retina.
The space shuttle is accelerated off its launch pad to a velocity of 525 m/s in 18.0 seconds.
What is its average acceleration?
Answer: 29.17m/s^2
Explanation:
Given the following :
Velocity = 525 m/s
Time = 18 seconds
Acceleration = change in Velocity with time
Using the motion equation:
v = u + at
Where v = final Velocity
u = Initial Velocity and t = time
Plugging our values
525 = 0 + a × 18
525 = 18(a)
a = 525 / 18
a = 29.166666
a = 29.17 m/s^2
the components and functionality of the event horizon telescope.
Answer:
The Event Horizon Telescope comprises of a an interconnection of radio observatories. These radio observatories work in unison and helps in efficient observation of radio sources associated with black holes with angular resolution in comparison to their event horizons. This equipment functions by ensuring that anything or light which goes through the event horizon cannot escape from the black hole. Instead there will be a continual falling towards the center of the black hole.