Answer:
Low Greenhouse Gas Emissions. ...
High Power Output. ...
Inexpensive Electricity. ...
Nuclear Energy Doesn't Rely on Fossil Fuels. ...
Economic Impact. ...
Back-end Environmental Impact. ...
Past History of Nuclear Accidents. ...
High Up-Front and End Stage Cost.
Um joalheiro recebe uma encomenda onde ele deve fazer alguns anéis de prata. Ele dispõe de um pedaço de 100 g de prata mas precisa derrete-lo para colocar a prata em moldes específicos e construir esses anéis. O principal problema desse procedimento é que a temperatura de fusão da prata é muito alta e requer condições especiais. A prata possui temperatura de fusão de 961 ºC, calor latente de fusão de 21 cal/g e calor específico no estado sólido igual a 0,056 cal/gºC. Determine a quantidade de calor aproximada para fundir as 100 g de prata sabendo que sua temperatura inicial é de 20°C. A 2,1 kcal B 0,5 kcal C 7,4 kcal D 5,3 kcal E 6,3 kcal
Answer:
Correct option: C -> 7.4 kcal
Explanation:
First we need to find the energy necessary to heat the silver from 20°C to 961°. The change in temperature is 961 - 20 = 941, so the energy necessary is:
941 * 0.056 * 100 = 5269.6 cal
Then, for the melting process, we will need:
21 * 100 = 2100 cal
So the total energy needed is:
5269.6 + 2100 = 7369.6 cal = 7.4 kcal
Correct option: C
Para mover un cuerpo, se le ata una cuerda y tres personas tiran de ella, ejerciendo fuerza de 60 Kgf, 70 Kgf y 75 Kgf. ¿Cuál es la resultante del sistema? (resuelve analítica y gráficamente). 6. Sobre una barra de 4,5 m de longitud, se ejercen fuerzas paralelas de igual sentido, si la resultante del sistema es hacia arriba y de 450 N y la fuerza mayor es de 250 N ¿Cuál es la intensidad de la otra fuerza? ¿A qué distancia de la resultante se encuentra cada fuerza?
Answer:
Assuming that the first person pulls with 0° direction, the second person pulls with 90° direction and the third person pulls with 180° direction, the net force would be
[tex]F=(60-75)i+70j\\F=-15i+70j[/tex]
It's module is
[tex]|F|=\sqrt{(-15)^{2} +(70)^{2} } =\sqrt{225+4900} \approx 71.6 \ KgF[/tex]
Therefore, the net force is 71.6 Kgf
Now, in the second problem, if the forces are parallel and have the same direction and sense, that means those forces complement each other, that means if the major one is 250 Newtons, then the second one is 200 Newtons, because the net force is 250 N.
Therefore, the missing force is 200 N.
Which is closer to the Sun—Mercury or the Earth? A. They are the same distance from the Sun. B. The Earth is closer to the Sun than Mercury is. C. Mercury is closer to the Sun than the Earth is. D. The distance from the Earth to the Sun cannot be determined.
Answer:
the answer is C
Explanation:
I know because mercury is the first planet closest to the sun
A car is going 60.0 mi/h and has to stop in 6.0 seconds. What is the car’s acceleration?
Explanation:
Convert mi/h to ft/s.
60.0 mi/h × (5280 ft/mi) × (1 h / 3600 s) = 88.0 ft/s
Find the acceleration.
a = Δv / Δt
a = (0 ft/s − 88.0 ft/s) / 6.0 s
a = -14.7 ft/s²
The driver must accelerate the car at the average rate of
- 10 mile / hour-second
for 6 seconds .
PLEASE HELP!!
Wildcats, such as the lynx, are predators of rabbits. Which will MOST likely occur if a new, aggressive species of wolf is introduced into the ecosystem that is a predator of the lynx?
A.The new species population will consume the food that the rabbits eat.
B.The population of the rabbits in the ecosystem will increase.
C.The new species population will be consumed by the lynx.
D.The population of the lynx in the ecosystem will increase.
ans a: wild cats
ans b:yes
Calculate the energy that 1.5 kg of mass contains
Answer:
[tex]4.5(10)^8[/tex] joules
Explanation:
Mass–energy equivalence is the principle that says that anything that has mass has an equivalent amount of energy. Converse is also true.
The relation between energy and mass is given by [tex]E=mc^2[/tex]
Here, E denotes energy, m denotes mass and c denotes speed of light
Mass [tex](m)=1.5\,\,kg[/tex]
Speed of light (c) = 3 × [tex]10^8[/tex] m/s
Therefore,
[tex]E=1.5(3)(10)^8=4.5(10)^8[/tex] joules.
The S.I. unit of energy is joules which is equal to [tex]1\,\,kg\,\,m^2/s^2[/tex]
Jada’s family pulls into a gas station. Her mother fills up the car’s tank with fuel from a pump. Jada notices this symbol on the pump.
Image shows a pump at a gas station with a symbol of corn on it.
What do you think the symbol indicates?
A. This gasoline is to be used only in farm vehicles.
B. It is not safe to have gasoline around food products.
C. This gasoline can also be used as a fertilizer to help plants grow.
D. A biomass has been used as part of the fuel.
Answer:
D- a biomass has been used as a part of the fuel.
what are polarized waves
Answer:
A light wave that is vibrating in more than one plane is referred to as unpolarized light.
Explanation:
A boat travels at 30 mph for a huge, solid cliff that is about 3,000 meters away. When the horn on the boat makes a toot, you can hear the initial sound directly from the horn and also an echo from the cliff wall some time later. How does the frequency of the echo compare with the frequency of the horn before the ship moved?
Group of answer choices
The frequency of the echo is slightly increased.
The frequency of the echo is slightly decreased.
The frequency is unchanged.
Not enough information to determine.
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat [tex]=30\ mph[/tex]
cliff is [tex]3000\ m[/tex] away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know [tex]time \propto \frac{1}{frequency}[/tex]
therefore frequency of the echo slightly decreased.
A boat at anchor is rocked by waves whose crests are 28 m apart and whose speed is 7 m/s. How often do these waves reach the boat? State your answer in terms of frequency (Hz) and period T (seconds).
Answer:
0.25 Hz
4 s
Explanation:
Speed = wavelength × frequency
7 m/s = 28 m × f
f = 0.25 Hz
Frequency = 1 / period
0.25 Hz = 1 / T
T = 4 s
David delivers meals to elderly people once a week. He uses a cart to move the meals. The cart has four smooth wheels. Which type of friction acts between the cart wheels and the sidewalk?
A. sliding friction
B. rolling friction
C. fluid friction
D. static friction
Answer:Rolling
Explanation:
Since the wheels roll, the wheels do not rub against the sidewalk, So it cannot be sliding. The wheels are not a liquid, and there shouldnt be any static.
Read the scenario. A car starts 10 m north of a reference point. It moves at a constant velocity over the next 5 s, reaching a position of 10 m south of the reference point. What is the car’s average velocity? 2 m/s south 4 m/s north 0 m/s 4 m/s south
Answer:
4 m/s south
Explanation:
This is a pretty easy one.
Assume that the car has a reference point ragged x
We also know that the car starts moving at a point 10 m North of X. It moves steadily at a uniform velocity and ended at a position 10 m south of X.
If x is the reference point, we can infer that the car moves a total distance of, 10 m + 10 m.
Thus, the total distance moved by the car is 20 m.
It is also stated that it achieves that distance in 5 seconds.
Velocity is defined as the ratio of distance with respect to the tome taken, i.e V = d/t
Then, the velocity is
V = 20 / 5 = 4 m/s
Considering the fact that the car left and moved towards the south. We can say that it moved 4 m/s South.
How is a problem and solution text
structure different from a cause and
effect text structure?
Which has greater kinetic energy: a bullet that has a mass of 0.05 kg travelling at 2500 m/s, or a lorry that has a mass of 4500 kg and is moving at 50 m/s?
Answer:
its the lorry
Explanation:
The kinetic energy of the truck will be, 5625000 kg m/s and the kinetic energy of the bullet will be 156250 kg m/s. So the kinetic energy of the lorry will be higher than the kinetic energy of the Bullet.
What is Kinetic Energy?Kinetic energy is a type of energy that a particle or an object possesses as a result of its motion. By exerting a net force on an item, work is done, which transfers energy; as a result, the object accelerates and obtains kinetic energy.
A moving item or particle's ability to move depends on both its mass and velocity. This is known as kinetic energy. Translation (or movement along a path from one location to another), rotation about an axis, vibration, or any combination of motions are examples of possible types of motion.
According to the question,
K.E of the lorry: 1/2 (4500)(50)²
K.E of the lorry = 5625000 kg m/s.
K.E of the bullet: 1/2(0.05)(250)²
K.E of the bullet = 156250 kg m/s
Hence, the kinetic energy of the lorry is greater than the kinetic energy of the bullet.
To get more information about Kinetic Energy :
https://brainly.com/question/12669551
#SPJ2
What is power?
A. a magnitude of a force needed to move an object
B. how much work can be done in a given time
C. the distance over time that an object moves
D, The energy needed to create work
Answer:
The answer is B.
Explanation:
The formula of power is :
[tex]power = \frac{work \: done}{time} [/tex]
* Work done can be "Energy"
What is the current in a 160V circuit if the resistance is 2Ω?
Answer:
80 amperes
Explanation:
Current = Voltage/Resistance
160/2 = 80
How does visible light interact with objects to produce the colors we see?
Answer:
Visible light when all put together is white. When objects appear to be, lets say, red, it would be the only color not absorbed by that object. same goes with all other colors. So black objects absorb all colors (not 100%) and that is why black clothing gets hotter, it simply absorbs all incoming light, as apposed to white that will reflect the colors back, making all of them together appear white. Hope this helps, not the best at explaining things.
You arrive in my class 45 seconds after leaving math which is 90 meters away. How fast did you travel?
Answer:
2m/s
Explanation:
speed = distance÷time
speed =90÷45=2m/s
Solving elastic collisions problem the hard way
Answer:
Solving elastic collisions problem the hard wayExplanation:
perfect drawing
A rocket, launched from rest, steadily increases speed to 33m/s over a 3.6s
interval before exhausting all the fuel. The rocket continues upward but slows
steadily to a stop 2.8s after running out of fuel.
How far did the rocket rise while burning fuel?
Answer:4 miles
Explanation:
When a warm air mass and cold air mass come together, like a warm front and cold front, a typical outcome is rain. What explains why rain forms in this situation?
A. The cold air causes the moisture in the warm air to condense and precipitate as rain.
B. The cold air is moving faster than the warm air, which causes rain.
C. Because the cold air is denser, it causes rain.
D. The two air masses neutralize each other, which results in clouds that produce rain.
Answer:
A,when the two air masses meet,the cold air cools the block if warm air,causing it to condense and form stratus clouds( blankets of blank clouds that form when air rises slowly e.g. a warm air mass meets a cold one). Eventually when the cloud becomes saturated precipitation falls from them(precipitation is moisture in any form that falls from the atmosphere).
An astronaut's training centrifuge has a radius of 4.0m. If it goes round once every 2.5s, calculate the velocity of the end of the centrifuge arm (4.0m from the pivot).
Answer: 10.048m/s
Explanation:
We know that the radius is r = 4.0m
And for rotating things, the tangential velocity (or the velocity of the end of the centrifuge arm) can be calculated as:
v = r*w
The period is T = 2.5s,
This means that if sin(w*t) describes this situation, we have that:
sin(w*t) = sin(w*(t + T))
and we know that:
sin(w*0) = 0
sin(w*(0 + T)) = Sin(w*T) = 0
this means that w*T = 2*pi
w = 2*pi/T = 2*pi/2.5s = (2*3.14)/2.5 s = 2.512 hz
Then the velocity can be calculated as
v = r*w = 4.0m*2.512hz = 10.048m/s
What might be collected to monitor the amount of excess nitrogen in the local water system
Answer:
If excess nitrogen is found in the crop fields, the drainage water can introduce it into ... have aquifers that can supply a lot of freshwater very near the land surface.
investigating sound waves lab please help!
Answer:first u have to figure out what the topic is then look for a rubric draft
Explanation:
Mg + __HCl → MgCl2 + H2
What coefficient is needed to balance the equation?
Answer:
The coefficient of the blank is 2
Explanation:
The balanced equation is Mg + 2HCl -> MgCl2 + H2 .
Answer:
Mg + 2HCl → MgCl2 + H2
Explanation:
. How does the intensity of sunlight received affect Earth’s temperatures?
explain how muscles and bones work together to help bend the arm.
By contracting, muscles pull on bones and allow the body to move. ... For example, the biceps and triceps muscles work together to allow you to bend and straighten your elbow. When you want to bend your elbow, your biceps muscle contracts (Figure below), and, at the same time, the triceps muscle relaxes.
Answer:
By contracting, muscles pull on bones and allow the body to move. ... For example, the biceps and triceps muscles work together to allow you to bend and straighten your elbow. When you want to bend your elbow, your biceps muscle contracts (Figure below), and, at the same time, the triceps muscle relaxes.
Each gas sample has the same temperature and pressure. which sample occupies the greatest volume? each gas sample has the same temperature and pressure. which sample occupies the greatest volume? 40.0 gar 20.0 gne 20.0 gh2 4.0 ghe
Answer:
20 gram of H as the greastest volume
Explanation:
Each gas sample has the same temperature and pressure. which sample occupies the greatest volume? each gas sample has the same temperature and pressure. which sample occupies the greatest volume? 40.0 gar 20.0 gne 20.0 gh2 4.0 ghe
Given that,
40.0 g of Ar
20.0 g of Ne
20.0 g of h
24.0 g of he
The ideal gas equation ; Pv = nRT
where P is the pressure, V is the volume, R is the gas constant, T is the temperature, n is the number of mole
which is equal to
n = m / M
where m is the given mass
M is the molar mass
The given gas sample are at the same temperature and pressure,
So, the temperature, pressure and gas constant are fixed.
Therefore the volume is proportional to the given mass and molar mass
V ∝ m/M
Substitute the given mass and molar mass of given masses for comparison
No of mole of Ar = mass / molar mass
= 40 / 40 = 1 mole
No of mole of Ne = mass / molar mass
= 20 / 20 = 1 mole
No of mole of h = mass / molar mass
= 20 / 1 = 20 mole
No of mole of he = mass / molar mass
= 24 / 4 = 6 mole
Hence, 20 gram of H as the greastest volume
explain how muscles and bones work together to help bend the arm.
Answer:
Bones make sure the arms structure is stable while the muscle is the one actively moving it and carrying out actions.
a 25 ohm resistor in an electric circuit draws a current of 5 amperes a certain amount of charge through the resistor in 36 seconds calculate the voltage
Answer:
V= 125volts
Explanation:
R =25ohms
I = 5 amp
V = ?
t = 36seconds
V = IR
V = 5× 25
V= 125volts
Q = It
Q = 5×36
Q = 180 coulombs
Q is the amount of charge.