Answer:
I don't know if these are the biggest but they are burning fossil fuels factories that release CO2 driving cars and cutting down trees.
Calculate conductance of a conduit the cross-sectional area of which is 1.5 cm2 and the length of which is 9.5 cm, given that its conductivity is 0.65 ohm-1 cm-1.
0.15 ohm-1
0.10 ohm-1
1.2 ohm-1
7.5 ohm-1
Answer:
1.2
Explanation:
Explain whether or not you would trust any conclusions obtained from this data. When formulating your answer, consider whether or not the effects of friction could account for the results these students obtained. What could the students have done wrong
Answer:
Please find the complete question in the attached file.
Explanation:
This graph as seen in the question must not be trusted. The reason for this is the plotted line of genesis desnt.
F=Ma
When F is in the axis (x,y) and mass of the system of the arc must be plotted F = 0 if a = 0 is considered as the perfectly friction-less ground.
This might be the case, as noted correctly, with such a surface tension opposite our twisting motion, in there is a coercing vertex even when the velocity of the body is zero, that is an example of friction force where the beginning pressure is working against frictional without moving or speeding up the body.
Concerning whatever the students got right, the complete experiment I knew is only evaluated correctly, but some of the suggestions clean the surface before exp, place the oil surface film and doing the experiment on an emptied ship; minimize that friction component.
In which area of the sun does gas rise as it heats up, then fall back down as it cools
The convection zone is the area of the sun does gas rise as it heats up, then fall back down as it cools.
What is Convection zone?This part of the Sun is found below the photosphere and helps isn the area where the form of heat transfer known as Convection takes place.
This occurs when heated gases rise up and then falls back when cooled as a result if hot gases being less dense.
Read more about Convection zone here https://brainly.com/question/22542880
How could extreme heat (resulting from Climate Change) affect human and
animal life?
Answer: See explanation
Explanation:
Climate change, is also referred to as global warming, and it simply means the rise in Earth's average surface temperature.
Effects of climate change include rising sea levels, heat waves, drought, storms, etc.
Extreme heat events is dangerous to the health of both animals and humans. For human beings, it can bring about increase in heat- related illness, weakness, heat stroke and excessive water consumption.
For animals, it can lead to struggling of the animals in losing their excess body heat by evaporation. Other effects include panting, loss of appetite, increased drinking, difficulty breathing, anxious behaviour, and weakness.
At a distance of 8 m, the sound intensity of one speaker is 66 dB. If we were to place 3 speakers in a circle of radius 8 m, what woud the sound intensity level be at the center of the circle
Answer:
dβ = 70. 77 dβ
Explanation:
The intensity of sound in decibels is
dβ = 10 log I/I₀
let's look for the intensity of this signal
I / I₀ = 10 dβ/10
I / I₀ = 3.981 10⁶
the threshold intensity of sound for humans is I₀ = 1 10⁻¹² W / m²
I = 3.981 10 ⁶ 1 10⁻¹²
I = 3,981 10⁻⁶ W / m²
It is indicated that 3 cornets are placed in the circle, for which total intensity is
I_total - 3 I
I_total = 3 3,981 10⁻⁶
I_total = 11,943 10⁻⁶ W / m²
let's reduce to decibels
dβ = 10 log (11,943 10⁻⁶/1 10⁻¹²)
dβ = 10 7.077
dβ = 70. 77 dβ
¿Es posible que un objeto se mueva en
una dirección distinta de la dirección de la fuerza neta
que actúa sobre el objeto?
Answer:
translate it to English plss
An aircraft is in level flight at 225 km/hr through air at standard conditions. The lift coefficient at this speed is 0.45 and the drag coefficient is 0.065. The mass of the aircraft is 900 kg. Calculate the effective lift area for the aircraft and the required engine thrust and power to maintain level flight.
Answer:
- the effective lift area for the aircraft is 8.30 m²
- the required engine thrust is 1275 N
- required power is 79.7 kW
Explanation:
Given the data in the question;
Speed V = 225 km/hr = 62.5 m/s
The lift coefficient CL = 0.45
drag coefficient CD = 0.065
mass = 900 kg
g = 9.81 m/s²
a) the effective lift area for the aircraft
we know that for a steady level flight, weight = lift and thrust = drag
Using the equation for the lift force
F[tex]_L[/tex] = C[tex]_L[/tex][tex]\frac{1}{2}[/tex]ρV²A = W
we substitute
0.45 × [tex]\frac{1}{2}[/tex] × 1.21 × ( 62.5 )² × A = ( 900 × 9.81 )
1081.05 × A = 8829
A = 8829 / 1081.05
A = 8.30 m²
Therefore, the effective lift area for the aircraft is 8.30 m²
b) the required engine thrust and power to maintain level flight.
we use the expression for drag force
F[tex]_D[/tex] = T = C[tex]_D[/tex][tex]\frac{1}{2}[/tex]ρV²A
we substitute
= 0.065 × [tex]\frac{1}{2}[/tex] × 1.21 × ( 62.5 )² × 8.30
T = 1275 N
Since drag and thrust force are the same,
Therefore, the required engine thrust is 1275 N
Power required;
P = TV
p = 1275 × 62.5
p = 79687.5 W
p = ( 79687.5 / 1000 )kW
p = 79.7 kW
Therefore, required power is 79.7 kW
Two electrons in adjacent atomic shells are separated by a distance of 6.64 ✕ 10−11 m. (a) What is the magnitude of the electrostatic force between the electrons? N (b) What is the ratio of the electrostatic force to the gravitational force between the electrons? FE FG =
Answer:
The ratio of the electrostatic force to the gravitational force between the electrons is 4.181 x 10⁴²
Explanation:
Given;
charge of electron, Q = 1.602 x 10⁻¹⁹ C
mass of an electron, m = 9.1 x 10⁻³¹ kg
distance between the two electrons, r = 6.64 x 10⁻¹¹ m
The electrostatic force between the electrons is calculated using Coulomb's law;
[tex]F_e = \frac{kQ^2}{r^2} \\\\F_e = \frac{(9\times 10^9)(1.602 \times 10^{-19})^2}{(6.64 \times 10^{-11})^2} \\\\F_e = 5.239 \times 10^{-8} \ N[/tex]
The gravitaional force between the electrons is calculated as;
[tex]F_g = \frac{Gm^2}{r^2} \\\\F_g = \frac{(6.67\times 10^{-11})(9.1 \times 10^{-31})^2}{(6.64\times 10^{-11})^2} \\\\F_g = 1.253 \times 10^{-50} \ N[/tex]
The ratio of the electrostatic force to the gravitational force between the electrons;
[tex]\frac{F_e}{F_g} = \frac{5.239\times 10^{-8}}{1.253 \times 10^{-50}} = 4.181 \times 10^{42}[/tex]
You instead want to make sure the battery for your string of lights will last as long as possible. A battery will last longer if it powers a circuit with low current. How could you hook up a battery and 2 light bulbs so the least amount of current flows through the battery? Use the measurement tools in the simulation to check your design.
Answer:
Put the 2 light bulbs in series.
Explanation:
The resistance will be the greatest if you hook up the light bulb in series, and since resistance and current are inversely proportional, the current will be the least as well.
an inclined plane rises to a height of 2m over a distance of 6m calculate the angle of the slope
Answer:
Explanation:
Slope is rise over run and, consequently, it is also the tangent ratio. the side measuring 2 is the height of the right triangle that is formed by the inclined plane (the hypotenuse), the height, and the base (the ground or surface that the plane is sitting on). If we use the tangent ratio,
[tex]tan\theta=\frac{2}{6}=\frac{1}{3}[/tex] so
[tex]tan^{-1}(\frac{1}{3})=\theta[/tex] so
θ = 18.4 which is also the angle that makes that slope.
a ball rolls off the edge of a 2m high shelf at a speed of 5 m/s and hits the ground the taken to hit the ground is
Answer:
Explanation:
Use the one-dimensional equation
Δx = [tex]v_0t+\frac{1}{2}at^2[/tex] where delta x is the displacement of the object, v0 is the velocity of the object, a is the pull of gravity, and t is the time in seconds. That's our unknown.
Δx = -2 (negative because where it ends up is lower than the point at which it started),
[tex]v_0=5[/tex], and
a = -9.8
Filling in:
[tex]-2=5t+\frac{1}{2}(-9.8) t^2[/tex] and simplified a bit:
[tex]-2=5t-4.9 t^2[/tex]
this should look hauntingly familiar (a quadratic, which is parabolic motion...very important in physics!!). We begin by getting everything on one side of the equals sign and solving for t by factoring:
[tex]-4.9 t^2+5t+2=0[/tex] (the 0 is also indicative of the object landing on the ground! Isn't this a beautiful thing, how it all just works so perfectly together?)
When you factor this however your math/physics teacher has you factoring you will get that
t = 1.3 sec and t = -.31 sec
Since we all know that time can NEVER be negative, it takes the ball 1.3 sec to hit the ground from a height of 2 m if it is rolling off the shelf at 5 m/s.
A 0.20-kg block and a 0.25-kg block are connected to each other by a string draped over a pulley that is a solid disk of inertia 0.50 kg and radius 0.10 m. When released, the 0.25-kg block is 0.21 m off the ground. What speed does this block have when it hits the ground?
Answer:
The answer is "0.2711 m/s".
Explanation:
Potential energy = Kinetic energy + Potential energy
[tex]m_1 gh =\frac{1}{2} m_1v^2 +\frac{1}{2} m_2v^2 + \frac{1}{2} I\omega^2 + m_1gh\\\\[/tex]
[tex](m_1- m_2)gh =\frac{1}{2} m_1v^2 +\frac{1}{2} m_2v^2 +\frac{1}{2} I\omega^2\\\\2(m_1 - m_2)gh = m_1v^2 + m_1v^2 + I\omega^2\\\\solid \ disk (I) = \frac{1}{2} \ \ M r^2 \\\\[/tex]
When there is no slipping, \omega =\frac{ v]{r}\\\\
[tex]2(m_1 - m_2)gh = m_1v^2 + m_2v^2 + (\frac{1}{2} Mr^2) (\frac{v}{r})^2\\\\2(m_1 -m_2)gh = m_1v^2 + m_2v^2 + \frac{1}{2} Mv^2\\\\4(m_1 -m_2)gh = 2m_1v^2 + 2m_2v^2 + Mv^2\\\\4(m_1 - m_2)gh = (2m_1 + 2m_2 + M) v^2\\\\[/tex]
[tex]v^2 = \frac{4(m_1 - m_2)gh}{(2m_1 + 2m_2 + M)}v[/tex]
[tex]v^2 = \frac{4 (0.25 \ kg - 0.20 \ kg) (9.8 \frac{m}{s^2}) (0.21 m)}{ (2 \times 0.25 kg + 2 \times 0.20 kg + 0.50 kg)}[/tex]
[tex]=\frac{0.1029}{1.4} \ \ \frac{m^2}{s^2}\\\\=0.0735\ \ \frac{m^2}{s^2}\\\\= 0.2711 \ \frac{m}{s}[/tex]
a ball dropped from a height of 10 meters will bounce more times before coming to rest than a ball dropped from a height of 5 meters. Use evidence and scientific reasoning to explain this phenomenon.
Answer:
plz mark brainliest again lol :)
Explanation:
When you drop a ball from a greater height, it has more kinetic energy just before it hits the floor and stores more energy during the bounce—it dents farther as it comes to a stop.
Answer:
When you drop a ball from a greater height, there is more potential energy. When you release the ball, the potential energy turns into kinetic energy. When the ball bounces off the ground, the ball go upward and then it has more potential energy. Then when it goes down it has more kinetic energy. The ball keeps doing this until there is not enough potential energy left.
Explanation:
Người ta đúc một khối nhóm (A) và một khối sắt ( (Fe) hình khối với cũng khói lượng 5 kg Khối lượng riêng (2) của Al và Fe là 2 rho ki =2.7*10^ 3 kg/m^ 3 ; mu 4 =7,8*10^ 3; kg/m^ 3 Hỏi, khối vật liệu nào có kích thước lớn hơn? (a) khối nhằm (b) khối sắt (c) hai khối có cùng kích cỡ
(A)
(B)
(C)
(D)
Which graph is a quadratic graph?
OA graph A
OB. graph B
OC graph
OD. graph D
How large must the coefficient of static friction be between the tires and road if a car is to round a level curve of radius 125 m at a speed of 95km/h
Answer:
673km
Explanation:
A tortoise and hare start from rest and have a race. As the race begins, both accelerate forward. The hare accelerates uniformly at a rate of 1.2 m/s2 for 4.5 seconds. It then continues at a constant speed for 12.1 seconds, before getting tired and slowing down with constant acceleration coming to rest 87 meters from where it started. The tortoise accelerates uniformly for the entire distance, finally catching the hare just as the hare comes to a stop. 1) How fast is the hare going 3.6 seconds after it starts
Answer:
[tex]v=4.32m/s[/tex]
Explanation:
From the question we are told that:
Accelerates at rate of [tex]1.2m/s^2[/tex]
Acceleration time [tex]t_a=4.5secs[/tex]
Velocity time 1 [tex]t_{v1}=12.1secs[/tex]
Deceleration distance [tex]d_a=87meters[/tex]
Generally the Newton's equation for motion is mathematically given by
[tex]V=at[/tex]
[tex]v=(1.2)3.6[/tex]
[tex]v=4.32m/s[/tex]
Keeping the mass at 1.0 kg and the velocity at 10.0 m/s, record the magnitude of centripetal acceleration for each given radius value. Include units. Radius: 2.0 m 4.0 m 6.0 m 8.0 m 10.0 m Acceleration: Radius factor: Acceleration factor:
Answer:
The centripetal acceleration for the first radius; 2.0 m = 50 m/s²
The centripetal acceleration for the second radius; 4.0 m = 25 m/s²
The centripetal acceleration for the third radius; 6.0 m = 16.67 m/s²
The centripetal acceleration for the fourth radius; 8.0 m = 12.5 m/s²
The centripetal acceleration for the fifth radius; 10.0 m = 10 m/s²
Explanation:
Given;
mass of the object, m = 1 kg
velocity of the object, v = 10 m/s
different values of the radius, 2.0 m 4.0 m 6.0 m 8.0 m 10.0 m
The centripetal acceleration for the first radius; 2.0 m
[tex]a_c = \frac{v^2}{r} \\\\a_c_1= \frac{(10)^2}{2} \\\\a_c_1= 50 \ m/s^2[/tex]
The centripetal acceleration for the second radius; 4.0 m
[tex]a_c_2= \frac{(10)^2}{4} \\\\a_c_2= 25 \ m/s^2[/tex]
The centripetal acceleration for the third radius; 6.0 m
[tex]a_c_3= \frac{(10)^2}{6} \\\\a_c_3= 16.67 \ m/s^2[/tex]
The centripetal acceleration for the fourth radius; 8.0 m
[tex]a_c_4= \frac{(10)^2}{8} \\\\a_c_4= 12.5 \ m/s^2[/tex]
The centripetal acceleration for the fifth radius; 10.0 m
[tex]a_c_5= \frac{(10)^2}{10} \\\\a_c_5= 10 \ m/s^2[/tex]
How do we get heat on Earth? Does thermal energy travel directly from the sun?
Why do nuclear power plants use fission rather than fusion to generate
electric energy?
A. Fusion requires very high pressure and temperature.
B. A problem might lead to an explosion in a fusion reactor, but not
in a fission reactor.
C. The isotope used in fission is more common than the one used
in fusion.
D. Fission produces less radioactive waste than fusion does.
Answer:
Fission is used in nuclear power reactors since it can be controlled, while fusion is not utilized to produce power since the reaction is not easily controlled and is expensive to create the needed conditions for a fusion reaction.
Explanation:
Answer:
Hello There!!
Explanation:
I think it is A. Fusion requires very high pressure and temperature. Sorry if I am wrong.
hope this helps,have a great day!!
~Pinky~
A 45.00 kg person in a 43.00 kg cart is coasting with a speed of 19 m/s before it goes up a hill.Assuming there is no friction, what is the maximum vertical height the person in the cart can reach?
Answer:
the maximum vertical height the person in the cart can reach is 18.42 m
Explanation:
Given;
mass of the person, m₁ = 45 kg
mass of the cart, m₂ = 43 kg
velocity of the system, v = 19 m/s
let the maximum vertical height reached = h
Apply the principle of conservation mechanical energy;
[tex]P.E = K.E\\\\mgh_{max} = \frac{1}{2} mv^2_{max}\\\\gh_{max} = \frac{1}{2} v^2_{max}\\\\h_{max} = \frac{v_{max}^2}{2g} \\\\h_{max} = \frac{19^2}{2\times 9.8} \\\\h_{max} = 18.42 \ m[/tex]
Therefore, the maximum vertical height the person in the cart can reach is 18.42 m
A superconductor performs best at ______.
Extremely high temperatures
Room temperature
Very cold temperatures
Any temperature
Answer:
c
Explanation:
Superconductors perform best at very cold temperatures because resistivity of this kind of materials decays drastically with temperature. Chromium is most likely to be the best conductor of electricity because it belongs to the Transition Metal group of the periodic table
Two long, straight wires are fixed parallel to one another a distance do apart. The wires carry equal constant currents 1, in the same direction. The attractive magnetic force per unit length between them if f = F/L. What is the force per unit length between the wires if their separation is 2d, and each carries current 210? 10 da lo A. f/4 B. f/2 C. 3f/2 D. 2f
Answer:
The option (B) is correct.
Explanation:
The magnetic force between the two current carrying wires is given by
[tex]F =\frac{\mu o}{4\pi}\times \frac{2 I I'}{r}[/tex]
where, I and I' be the currents in the wires and r is the distance between the two wires.
Here, we observe that the force between the wires is inversely proportional to the distance between them.
So, when the distance is doubled , let the new force is F'.
[tex]\frac{F'}{F}=\frac{r}{r'}\\\\\frac{F'}{F}=\frac{d}{2d}\\\\F'=\frac{F}{2}[/tex]
So, option (B) is correct.
A person pushes a 15.7-kg shopping cart at a constant velocity for a distance of 25.9 m on a flat horizontal surface. She pushes in a direction 23.7 ° below the horizontal. A 32.7-N frictional force opposes the motion of the cart. (a) What is the magnitude of the force that the shopper exerts? Determine the work done by (b) the pushing force, (c) the frictional force, and (d) the gravitational force.
Answer:
a) F = 35.7 N, b) W = 846.7 J, c) W = - 846.9 J, d) W=0
Explanation:
a) For this exercise let's use Newton's second law, let's set a reference frame with the x-axis horizontally
let's break down the pushing force.
cos (-23,7) = Fₓ / F
sin (-237) = F_y / F
Fₓ = F cos 23.7 = F 0.916
F_y = F sin (-23.7) = - F 0.402
Y axis
N- W - F_y = 0
N = W + F 0.402
X axis
Fₓ - fr = 0
F 0.916 = fr
F = fr / 0.916
F = 32.7 / 0.916
F = 35.7 N
It is asked to calculate several jobs
b) the work of the pushing force
W = fx x
W = 35.7 cos 23.7 25.9
W = 846.7 J
c) friction force work
W = F x cos tea
friction force opposes movement
W = - fr x
W = - 32.7 25.9
W = - 846.9 J
d) The work of the force would gravitate, as the displacement and the force of gravity are at 90º, the work is zero
W = 0
The conversion of thermal energy into mechanical energy requires
a thermometer.
D. Beat engine
C vaporizer.
d thermostat.
A firefly glows by the direct conversion of chemical energy to light. The light emitted by a firefly has peak intensity at a wavelength of 550 nm. Part A What is the minimum chemical energy, in eV, required to generate each photon
Answer:
Explanation:
The energy of a photon is given by the Planck relation
E = h f
the speed of light is related to wavelength and frequency
c = λ f
f- c /λ
we substitute
E = h c /λ
let's calculate
E = 6.63 10-34 3 10⁸ / 550 10-9
E = 3.616 10-19 J
let's reduce to eV
E = 3.616 10-19 J (1 eV / 1.6 10-19)
E = 2.26 eV
A man is pushing a box of weight W with a forward force of magnitude F. The box
moves forward with a constant speed. What is the magnitude f of the friction force?
Answer:
The magnitude of the friction force is also F.
Explanation:
By the second Newton's law, we know that:
F = m*a
Net force is equal to mass times acceleration.
Here, we know that the box moves with constant speed, thus, the box has no acceleration, then the net force applied to the box is zero.
Also, remember that the friction force is given by:
[tex]F_f = -\mu*W[/tex]
Where mu is the coefficient of friction, and this force opposes to the direction of motion (that coincides with the direction of our forward force, that is why this has a negative sign)
The net force will be equal to the sum of our two horizontal forces (as the weight is already canceled by the normal force)
[tex]F_{total} = F + F_f[/tex]
And this is equal to zero, because we know that the box is non-accelerated.
Then we must have that:
[tex]F_f = -F[/tex]
Then we can conclude that the magnitude of the friction force is F.
What is the difference between muscular strength and muscular endurance
How much power is required to light a lightbulb at 100V of voltage when the lightbulb has a resistance of 500 Ohms?
Answer:
20 Watt
Explanation:
Applying
P = V²/R................... Equation 1
Where V = Voltage, P = Power, R = resistance
From the question,
Given: V = 100V, R = 500 ohms
Substitute these values into equation 1
P = (100²)/500
P = 10000/500
P = 20 Watt.
Hence the power required to light the bulb is 20 W
A rocket moving around the earth at height "H", If the gravitational acceleration "g1" at height
His of gravitational acceleration 'g at earth surface. If Earth radius is "R", find "H"
using R
Answer:
At the earth's surface g = G M / R^2 where G is the gravitational constant
at H g1 = G M / (R + H)^2 using Gauss' theorem for enclosed mass
g1 = G M / (R^2 + 2 R H) ignoring H^2 as it is small compared to R^2
g / g1 = (R^2 + 2 R H) / R^2 = 1 + 2 R H
g = g1 + 2 R H g1
g1 - g = - 2 R H or H = (g1 - g) / 2 R