Answer:
The algorithm
Step 1: Start
Step 2: Input Radius
Step 3: While Radius < = 0
Input Radius
Step 4: Pi = 3.14
Step 5: Perimeter = 2 * Pi * Radius
Step 6: Area = Pi * r^2
Step 7: Print Area, Perimeter
Step 8: Stop
Explanation:
This indicates the start of the algorithm
Step 1: Start
This inputs the radius
Step 2: Input Radius
The following loop is repeated until user input for radius is greater than 0
Step 3: While Radius < = 0
Input Radius
This initializes Pi to 3.14
Step 4: Pi = 3.14
This calculates the Perimeter or Circumference
Step 5: Perimeter = 2 * Pi * Radius
This calculates the Area
Step 6: Area = Pi * r^2
This prints the calculated Perimeter ad Area
Step 7: Print Area, Perimeter
This indicates the end of the algorithm
Step 8: Stop
I've added the flowchart as an attachment
Find the wavelength of light that has its third minimum at an angle of 48.6º when it falls on a single slit of width 3.00 μm .
Answer:
750 nm
Explanation:
It is given that,
Third minimum is at an angle of 48.6º when it falls on a single slit of width 3.00 μm.
We need to find the wavelength of the light. For a single slit experiment, the relation between wavelength and slit width is given by :
[tex]d\sin\theta=n\lambda[/tex]
For third minimum, n = 3
[tex]\lambda=\dfrac{d\sin\theta}{n}\\\\\lambda=\dfrac{3\cdot10^{-6}\cdot\sin48.6}{3}\\\\\lambda=7.5\times 10^{-7}\ m\\\\\lambda=750\ nm[/tex]
So, the wavelength of light is 750 nm.
Acceleration is sometimes expressed in multiples of g, where g = 9.8 m/s^2 is the magnitude of the acceleration due to the earth's gravity. In a test crash, a car's velocity goes from 26 m/s to 0 m/s in 0.15 s. How many g's would be experienced by a driver under the same conditions?
Answer:
Acceleration = 18g
Explanation:
Given the following data;
Initial velocity, u = 26m/s
Final velocity, v = 0
Time = 0.15 secs
To find the acceleration;
In physics, acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.
Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.
Mathematically, acceleration is given by the equation;
[tex]Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}[/tex]
Substituting into the equation, we have;
[tex]a = \frac{0 - 26}{0.15}[/tex]
[tex]a = \frac{26}{0.15}[/tex]
Acceleration = 173.33m/s2
To express it in magnitude of g;
Acceleration = 173.33/9.8
Acceleration = 17.7 ≈ 18g
Acceleration = 18g
In the winter sport of curling, players give a 20 kg stone a push across a sheet of ice. The Slone moves approximately 40 m before coming to rest. The final position of the stone, in principle, onlyndepends on the initial speed at which it is launched and the force of friction between the ice and the stone, but team members can use brooms to sweep the ice in front of the stone to adjust its speed and trajectory a bit; they must do this without touching the stone. Judicious sweeping can lengthen the travel of the stone by 3 m.1. A curler pushes a stone to a speed of 3.0 m/s over a time of 2.0 s. Ignoring the force of friction, how much force must the curler apply to the stone to bring it op to speed?A. 3.0 NB. 15 NC. 30 N
D. 150 N2The sweepers in a curling competition adjust the trajectory of the slope byA. Decreasing the coefficient of friction between the stone and the ice.
B. Increasing the coefficient of friction between the stone and the ice.C. Changing friction from kinetic to static.D. Changing friction from static to kinetic.3. Suppose the stone is launched with a speed of 3 m/s and travel s 40 m before coming to rest. What is the approximate magnitude of the friction force on the stone?A. 0 NB. 2 NC. 20 ND. 200 N4. Suppose the stone's mass is increased to 40 kg, but it is launched at the same 3 m/s. Which one of the following is true?A. The stone would now travel a longer distance before coming to rest.B. The stone would now travel a shorter distance before coming to rest.C. The coefficient of friction would now be greater.D. The force of friction would now be greater.
Answer:82. Since you have a distance and a force, then the easiest principle to use is energy, i.e. work.
The work done by friction is F * d. This work cancels out the kinetic energy of the stone (1/2)mv^2
Fd = (1/2)mv^2
F = (1/2)mv^2/d.
Plug in m = 20 kg, v = 3 m/sec, d = 40 m.
83. With more mass, the kinetic energy is higher now. The work needed is higher. W = F * d and F is the same.
Explanation:Hope I helped :)
2. A force of 500 N separates two objects. The distance between their centers is 67 m. The first object has a mass of 20 kg. What is the mass of the second object?
Answer:
The Equation of Newton's Law of Gravity. G is called the Gravitational Constant, and has the value 6.67×10-11 N ∙m2kg-2 (N is for Newton, the physicists' unit of force)or 1.5×10-11 lb∙m2kg-2
Explanation:
Gravitational force is an attractive force that exists between all objects with mass . an object with mass attracts another object with mass.
Mass of second object is [tex]1.6825*10^{15}[/tex] kg
If two bodies have mass m₁ and m₂ . Then attractive force between them is calculated by formula show below,
[tex]F=G\frac{m1m2}{r^{2} }[/tex]
Where r is distance between bodies. and G is gravitational constant.
G = [tex]6.67*10^{-11}[/tex] [tex]Nm^{2}/kg^{2}[/tex]
Here, F = 500N, m₁=20 kg and r= 67 m
Substituting above values in force equation.
[tex]500=\frac{6.67*10^{-11}*20*m2 }{(67)^{2} } \\\\m2=1.6825*10^{15} Kg[/tex]
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why is a mountain ? what is a animal ? what is love ?
Answer:
When we love someone we experience the same positive thoughts and experiences as when we like a person. But we also experience a deep sense of care and commitment towards that person. Being “in love” includes all the above but also involves feelings of sexual arousal and attraction.
Explanation:
A plane mirror is placed to the right of an object. The image formed by the mirror will be a
real image that appears to be on the right of the mirror.
real image that appears to be on the left of the mirror.
virtual image that appears to be on the right of the mirror.
virtual image that appears to be on the left of the mirror.
Hamish is studying what happens when he sends a sound wave through different mediums, and he records his data in a table.
A 2-column table with 4 rows titled Hamish's Waves. The first column labeled Wave has entries 1, 2, 3, 4. The second column labeled Information has entries liquid, solid, gas, liquid.
Which statement could made about the data collected in Hamish’s table?
Wave 1 will move the fastest.
Wave 2 will move the slowest.
Wave 3 will move the slowest.
Wave 4 will move the fastest.
What is common between transverse waves and longitudinal waves?
Both include an amplitude, crest, and rarefactions
Both move faster at higher temperatures
Both move slower through densely packed molecules
Both include a wavelength from compression to compression
An angle of refraction is the angle between the refracted ray and the
incident ray.
normal.
medium.
boundary.
Answer:
A plane mirror is placed to the right of an object. The image formed by the mirror will be a virtual image that appears to be on the left of the mirror.
Explanation:
The x component of vector A is -25.0m and the y component id +40.0m (a) what is the magnitude of A?(b) What is the angle between the direction of A and the positive direction of x?
Answer:
θ = 122°
Explanation:
Components of a Vector
A vector in the plane can be defined by its rectangular components:
[tex]\vec A =<x,y>[/tex]
Or also can be given by its polar components:
[tex]\vec A =<r,\theta>[/tex]
Where r is the magnitude of the vector and θ is the angle it forms with the positive direction of x.
The relation between them is:
[tex]r=\sqrt{x^2+y^2}[/tex]
[tex]\displaystyle \theta=\arctan\frac{y}{x}[/tex]
It's given the x-component of vector A is x=-25 m and the y-component is y=40 m
(a)
The magnitude of the vector is:
[tex]r=\sqrt{(-25)^2+40^2}[/tex]
[tex]r=\sqrt{625+1600}[/tex]
[tex]r=\sqrt{2225}[/tex]
[tex]r\approx 47.2\ m[/tex]
(b)
[tex]\displaystyle \theta=\arctan\frac{40}{-25}[/tex]
[tex]\displaystyle \theta=\arctan (-1.6)[/tex]
The calculator gives us the value
θ = -58°
But the real angle lies on the second quadrant since x is negative and y is positive, thus:
θ = -58° + 180° = 122°
θ = 122°
4. A substance has a density of 0.79 g/cm'. It is soluble in water. List all the possibilities of what it might be How could you determine the actual identity?
Answer:
See explanation
Explanation:
Given that the density of the unknown substance is 0.79 g/cm3 and is soluble in water, the possible substances it could be are;
i) t-butanol
ii) ethanol
iii) 2-propanol
iv) acetone
However, the actual identity of the unknown substance can be obtained by carrying out a boiling point test. The four substances listed above have different boiling points. Hence the boiling point of the unknown substance ultimately discloses its identity.
20- A gram of distilled water at 4° C:
(a) will increase slightly in weight when heated to 6 C
(b) will decrease slightly in weight when heated to 6 C
(C) will increase slightly in volume when heated to 6 C
(d) will decrease slightly in volume when heated to 6 C
(e) will not change in either volume or weight
Answer:
D. will decrease slightly in volume when heated to 6° C
Explanation:
A gram of distilled water at 4° C will increase slightly in volume when heated to 6 C. Hence option C is correct.
What is Water ?Water has the chemical formula H2O, making it an inorganic substance. It is the primary chemical component of the Earth's hydrosphere and the fluids of all known living things (in which it serves as a solvent[1]). It is translucent, flavourless, odourless, and almost colourless. In spite of not supplying food, energy, or organic micronutrients, it is essential for all known forms of life. Its molecules are made up of two hydrogen atoms joined by covalent bonds and have the chemical formula H2O. The angle at which the hydrogen atoms are joined to the oxygen atom is 104.45°.[2] The liquid condition of H2O at normal pressure and temperature is known as "water" as well.
Water occurs because the environment on Earth is pretty near to the triple point of water.
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What is the de Broglie wavelength of an electron accelerated from rest through a potential difference of 50.0 V?
(a) 0.100 nm
(b) 0.139 nm
(c) 0.174 nm
(d) 0.834 nm
(e) none of those answers
Answer:
(c) 0.174 nm
Explanation:
According to de Broglie hypothesis, the wavelength of the wave associated with electron is given by:
[tex] \boxed{ \bf{\lambda = \sqrt{\dfrac{150}{V \ (in \ Volt)}} \: \text{\AA}}}[/tex]
V → Potential Difference (50.0 V)
By substituting value of potential difference in the equation, we get:
[tex] \rm \longrightarrow \lambda = \sqrt{\dfrac{150}{50}} \: \text{\AA} \\ \\ \rm \longrightarrow \lambda = \sqrt{3} \: \text{\AA} \\ \\ \rm \longrightarrow \lambda = 1.74 \: \text{\AA} \\ \\ \rm \longrightarrow \lambda = 0.174 \: nm[/tex]
A cube of wood having an edge dimension of 18.0 cm and a density of 651 kg/m3 floats on water.(a) What is the distance from the horizontaltop surface of the cube to the water level?(b) How much lead weight has to be placed on top of the cube sothat its top is just level with the water?
Answer:
A. 6.282
B. 2.03kg
Explanation:
A.
We solve using archimedes principle
L³pwood = L²dwater
We make d subject of the formula
d = Lpwood/pester
= 18x651/1000
= 18x0.651
= 11.718cm
Distance from horizontal top to water level
= 18-11.718
= 6.282cm
B.
When we place lead block
WL + L³pwoodg = L³pwaterg
WL = L³g(Pwater-Pwood)
= 0.18³x9.8(1000-651)
= 19.94N
19.94/9.8
= 2.03kg
The mass m is therefore 2.03kg
(a) The distance will be "6.282 cm".
(b) Mass will be "2.03 kg".
(a)
From Archimedes' principle, we get
→ [tex]L^3 \rho_{Wood} = L^2 d \rho_{Water}[/tex]
[tex]d = L \frac{\rho_{Wood}}{\rho_{Water}}[/tex]
[tex]= 18\times \frac{651}{1000}[/tex]
[tex]= 11.72 \ cm[/tex]
So,
The distance from horizontal top to the water level will be:
= [tex]18-11.72[/tex]
= [tex]6.282 \ cm[/tex]
(b)
After placing the lead block of weight [tex]W_L[/tex], we have
→ [tex]W_L +L^3 \rho_{Wood} g = L_3 \rho_{Water} g[/tex]
[tex]W_L = L^3 g(\rho_{Water}-\rho_{Wood})[/tex]
[tex]= 0.18^3\times 9.8\times (1000-651)[/tex]
[tex]= 19.94 \ N[/tex]
Mass,
m = 2.03 kg
Thus the above answer is right.
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Match the term to its correct definition:
____ 1. Test variable (independent variable)
A. This is what is being measured during a scientific investigation.
____ 2. Outcome variable (dependent variable)
B. This serves as a reference for comparison during a scientific investigation.
____ 3. Control group
C. This is what is being purposefully changed during the scientific investigation.
Answer:
1. C
2. B
3. A
Explanation:
Hope this helped!
If the net force acting on an object is not zero, then the object is definitely
at rest
moving with a constant velocity
being accelerated
losing mass
Answer:
C
Explanation:
Since the net force is changing, and not the speed, it is C
Hope this helped!
if on the average every man lives for 70 years, for how many microseconds is this life span
Answer:
3.1556926 × 10^13 microseconds
Explanation:
Hope this helped!
if on the average every man lives for 70 years, 3.1556926 × 10^13 microseconds is this life span
what is lifespan ?life span of an organism can be defined as the period of time between the birth and death of an organism, it is a common place that all organisms die.
Some of the organism die after a brief existence, for example mayfly, whose adult life burns out in a day, and the gnarled bristlecone pines, which have lived thousands of years.
The limits of the life span of each species appear to be determined by heredity, it can be locked within the code of the genetic material which are the instructions specify the age.
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Jessica pulls on a washing machine with 200 N of force. Mark helps out and pulls on the washing machine in the same direction with 400 N of force. What is the net force on the washing machine
Answer:
600N
Explanation:
Consider a person standing in an elevator that is moving at a constant velocity down. The upward normal force N exerted by the elevator floor on the person is Select one: a. smaller than the downward force of gravity on the person. b. identical to the downward force of gravity on the person. c. larger than the downward force of gravity on the person.
Answer:
b. identical to the downward force of gravity on the person.
Explanation:
For an object in an elevator,
F = mg - ma (g > a)
But since the velocity is uniform, a = 0.
Then,
F = mg - 0
F = mg
This is the actual weight of the object.
The object does not feel weightless, so that its actual weight can be measured during the downward motion of the elevator with uniform velocity.
Thus, the upward normal force, N, exerted by the elevator floor on the person is identical to the downward force of gravity on the person.
A student bought a 1.55-ounce chocolate bar and left it in
a car on a hot day.
How many ounces of chocolate are in the melted bar?
A. Exactly 1.55 ounces
B. At least 1.55 ounces
C. An unknown number of ounces
D. Less than 1.55 ounces
Answer:
a
Explanation:
A student bought a 1.55-ounce chocolate bar and left it in a car on a hot day. Exactly 1.55 ounces of chocolate are in the melted bar. Hence, option (A) is correct.
What is mass?In physics, mass is a quantitative measurement of inertia, a basic characteristic of all matter. It essentially refers to a body of matter's resistance to changing its speed or location in response to the application of a force.
The change caused by an applied force is smaller the more mass a body has. The kilogram serves as the unit of mass in the International System of Units (SI).
As mass does not depends on the state of the object, exactly same mass of chocolate are in the melted bar that it was in chocolate bar. So, 1.55 ounces of chocolate are in the melted bar. Hence, option (A) is correct.
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The Magnetic Dipole Moment of a Coil Problem A rectangular coil of dimensions 5.40 cm ✕ 8.50 cm consists of 25 turns of wire and carries a current of 20.0 mA. A 0.350 T magnetic field is applied parallel to the plane of the loop. A. What is the magnitude of its magnetic dipole moment?B. What is the magnitude of the torque acting on the loop?
Answer:
a
[tex]\mu = 0.0023 \ A\cdot m^2[/tex]
b
[tex]\tau = 0.00080 \ N \cdot m[/tex]
Explanation:
From the question we are told that
The dimensions of the rectangular coil is 5.40 cm ✕ 8.50 cm = 0.054 m X 0.085 m
The number of turns is [tex]N = 25 \ turns[/tex]
The current it is carrying is [tex]I = 20 \ mA = 0.02 \ A[/tex]
The magnetic field is [tex]B = 0.350 \ T[/tex]
Generally the magnitude of the magnetic dipole moment is mathematically represented as
[tex]\mu = N * I * A[/tex]
Here A is the area which is mathematically represented as
[tex]A = 0.054 * 0.085[/tex]
=> [tex]A = 0.00459 \ m^2[/tex]
So
[tex]\mu = 25 * 0.02 * 0.00459[/tex]
=> [tex]\mu = 0.0023 \ A\cdot m^2[/tex]
Generally the magnitude of the torque acting on the loop is mathematically represented as
[tex]\tau = \mu * B[/tex]
=>[tex]\tau = 0.0023 * 0.350[/tex]
=>[tex]\tau = 0.00080 \ N \cdot m[/tex]
describe three possible careers in physical science
Answer:
physical sicence boilagiy sxcience and earth science
Explanation:
A 5 kg bowling ball with a velocity of +10 m/s collides with a stationary 2 kg bowling pin. If the ball's final velocity is +8 m/s, what is the pin's final velocity?
a 5 m/s
b 2.5 m/s
c 10 m/s
d 5.2 m/s
Answer:
The pin's final velocity is 5m/sExplanation:
Step one:
given data
mass of ball m1=5kg
initial velocity of ball u1=10m/s
mass of pin m2=2kg
initial velocity of pin u2= 0m/s
final velocity of ball v2=8m/s
final velocity of pin v2=?
Step two:
The expression for elastic collision is given as
m1u1+m2u2=m1v1+m2v2
substituting we have
5*10+2*0=5*8+2*v2
50+0=40+2v2
50-40=2v2
10=2v2
divide both sides by 2
v2=10/2
v2=5m/s
The pin's final velocity is 5m/s
A man-made satellite of mass 6105 kg is in orbit around the earth, making one revolution in 430 minutes. What is the magnitude of the gravitational force exerted on the satellite by the earth? (The mass of the earth is 6.0 x 1024 kg and G = 6.67 x 10-11Nm2/kg2.
Answer:
A gravitational force of 6841.905 newtons is exerted on the satellite by the Earth.
Explanation:
At first we assume that Earth is represented by an uniform sphere, such that the man-made satellite rotates in a circular orbit around the planet. Hence, the following condition must be satisfied:
[tex]\left(\frac{4\pi^{2}}{T^{2}} \right)\cdot r = \frac{G\cdot M}{r^{2}}[/tex] (1)
Where:
[tex]T[/tex] - Period of rotation of the satellite, measured in seconds.
[tex]r[/tex] - Distance of the satellite with respect to the center of the planet, measured in meters.
[tex]G[/tex] - Gravitational constant, measured in newton-square meters per square kilogram.
[tex]M[/tex] - Mass of the Earth, measured in kilograms.
Now we clear the distance of the satellite with respect to the center of the planet:
[tex]r^{3} = \frac{G\cdot M\cdot T^{2}}{4\pi^{2}}[/tex]
[tex]r = \sqrt[3]{\frac{G\cdot M\cdot T^{2}}{4\pi^{2}} }[/tex] (2)
If we know that [tex]G = 6.67\times 10^{-11}\,\frac{N\cdot m^{2}}{kg^{2}}[/tex], [tex]M = 6.0\times 10^{24}\,kg[/tex] and [tex]T = 25800\,s[/tex], then the distance of the satellite is:
[tex]r = \sqrt[3]{\frac{\left(6.67\times 10^{-11}\,\frac{N\cdot m^{2}}{kg^{2}} \right)\cdot (6.0\times 10^{24}\,kg)\cdot (25800\,s)^{2}}{4\pi^{2}} }[/tex]
[tex]r \approx 18.897\times 10^{6}\,m[/tex]
The gravitational force exerted on the satellite by the Earth is determined by the Newton's Law of Gravitation:
[tex]F = \frac{G\cdot m\cdot M}{r^{2}}[/tex] (3)
Where:
[tex]m[/tex] - Mass of the satellite, measured in kilograms.
[tex]F[/tex] - Force exerted on the satellite by the Earth, measured in newtons.
If we know that [tex]G = 6.67\times 10^{-11}\,\frac{N\cdot m^{2}}{kg^{2}}[/tex], [tex]M = 6.0\times 10^{24}\,kg[/tex], [tex]m = 6105\,kg[/tex] and [tex]r \approx 18.897\times 10^{6}\,m[/tex], then the gravitational force is:
[tex]F = \frac{\left(6.67\times 10^{-11}\,\frac{N\cdot m^{2}}{kg^{2}} \right)\cdot (6105\,kg)\cdot (6\times 10^{24}\,kg)}{(18.897\times 10^{6}\,m)^{2}}[/tex]
[tex]F = 6841.905\,N[/tex]
A gravitational force of 6841.905 newtons is exerted on the satellite by the Earth.
At noon on a clear day, sunlight reaches the earth's surface at Madison, Wisconsin, with an average intensity of approximately 2.00 kJ·s−1·m^−2. If the sunlight consists of photons with an average wavelength of 510.0 nm, how many photons strike a 5.20 cm^2 area per second?
Answer:
The number of photons per second that strike the given area is 2.668 x 10⁸ photons/second
Explanation:
Given;
intensity of the sunlight, I = 2.00 kJ·s−1·m^−2
area of incident, A = 5.2 cm² = 5.2 x 10⁻⁴ m²
Energy of incident photons per second on the given area;
E = IA
E = (2000)( 5.2 x 10⁻⁴)
E = 1.04 J/s
Energy of a photon is given is by;
[tex]E = \frac{hc}{\lambda} \\\\E = \frac{(6.626*10^{-34})(3*10^8)}{(510*10^{-9})}\\\\E = 3.898*10^{-19} \ J/photon[/tex]
The number of photons per second that strike the given area is;
[tex]n = \frac{1.04 \ J/s}{3.898*10^{-19} \ J/photon} \\\\n = 2.668*10^{18} \ photons/second[/tex]
Therefore, the number of photons per second that strike the given area is 2.668 x 10⁸ photons/second
A force of 150 N is applied on an object at 60 degrees above the positive x-axis. Determine its
horizontal and vertical components.
Answer:
horizontal component=fcostita
=150cos60
use calculator to evaluate it
for vertical=fsintita
=150sin60
What average net force is required to accelerate a car with a mass of 1200 kg from rest to 27.0 m/s2 in 10.0 s ?
1620 N
4360 N
444 N
11800 N
3240 N
The average net force required to accelerate the car is 3240 N
What is acceleration?This is defined as the rate of change of velocity which time. It is expressed as
a = (v – u) / t
Where
a is the acceleration v is the final velocity u is the initial velocity t is the time How to determine the acceleration Initial velocity (u) = 0 m/sFinal velocity (v) = 27 m/sTime (t) = 10 sAcceleration (a) =?a = (v – u) / t
a = (27 – 0) / 10
a = 2.7 m/s²
How to determine the forceMass (m) 1200 KgAcceleration (a) = 2.7 m/s²Force (F) = ?F = ma
F = 1200 × 2.7
F = 3240 N
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How does Solar Energy impact the environment? Use in your own words.
Answer:
It helps to reduce polution and gasses that damage our good gases and the greenhouse gases. It produces energy from the sun. It is the cleanest way to go!
Explanation:
you drive your car at a speed of 40 km/hr then slow down to 30km/hr
Answer:
3
Explanation:
3
A small box slides down a ramp on a friction with surface. If the total energy of the system is conserved, which computational model expresses the kinetic energy of the box?
B. KEsubbox = Esubtotal - mgh
If you are modeling a system in which an object’s total energy is conserved, you could express potential energy as the difference between total and kinetic, or, alternatively, you could model kinetic energy as the difference between total and potential.
Why evaporation takes place from the Surface?
Answer:
in the water cycle evaporation occurs when the sunlight warms the surface of the water the heat from the sun makes the water molecules move faster and faster until they move so fast they can escape as a gas once evaporated a molecule from water that vapor spends about 10 days in the air
A car is traveling at 60 mph. If the rate of speed increases 4 mph each hour,
how long will it be before the car is traveling at a rate of 80 mph?
A) 4 hours
B) 5 hours
C) 6 hours
D 7 hours
Answer:
5 hours ................
Answer:
B=5 hrs
explanation:
becoz if you add 4 mph/hr
it will graually be 80 in 5 hrs
A tungsten filament at 25-degree celsius has a resistance of 0.350 ohms. What would be the resistance if the temperature is increased to 2850°C? The temperature coefficient of resistance for tungsten is 0.5*10^-3 /°C
Answer:
R₂₈₅₀ = 0.838 ohms
Explanation:
The resistance of an element at some other temperature than 0°C can be given by the following formula:
Rₓ = R₀(1 + ∝ΔT)
where,
Rₓ = Resistance at temperature x
R₀ = Resistance at 0°C
∝ = Coefficient of linear expansion of tungsten = 0.5 x 10⁻³ /°C
ΔT = Change in Temperature
So, for the resistance of tungsten wire at 25°C:
Rₓ = R₂₅ = 0.35 ohms
ΔT = 25°C
Therefore,
0.35 ohms = R₀[1 + (0.5 x 10⁻³ /°C)(25°C)]
R₀ = (0.35 ohms)/1.0125
R₀ = 0.345 ohms
Now, we find the resistance at 2850°C
R₂₈₅₀ = (0.345 ohms)[1 + (0.5 x 10⁻³ /°C)(2850°C)]
R₂₈₅₀ = 0.838 ohms