How can red giants be so bright when they are so cool
Answer:
The star's luminosity rises above its previous level. Because it is so cool, the surface will be red, and it will be much farther away from the center than it was during the earlier stages of star evolution. Despite its lower surface temperature, the red giant has a large surface area, which makes it very luminous.
If this decay has half-life of 2 years, how many years would it take for 10.8 g Protactinium-231 to remain given an initial mass of 86.3 g?
Answer:
Time = 6 years
Explanation:
First, we will calculate the no. of half life periods required to reduce the mass of Protactinium to the given value:
[tex]m' = \frac{m}{2^{n} } \\\\2^n = \frac{m}{m'}[/tex]
where,
n = no. of half-life periods = ?
m = initial mass = 86.3 g
m' = remaining mass = 10.8 g
Therefore,
[tex]2^n = \frac{86.3\ g}{10.8\ g}\\\\2^n = 8\\2^n = 2^3[/tex]
Since the bases are the same. Therefore equating powers:
n = 3
Now we calculate the time:
[tex]Time = (n)(Half-Life)\\Time =(3)(2\ years)[/tex]
Time = 6 years
Pedro is planning to model how changes in weather affect evaporation from lakes. For his first experiment, he wants to test how humidity affects the evaporation rate. He places one beaker with 300 mL of water in a dry area, and he places another beaker with 300 mL of water near a humidifier. Which of the following variables does Pedro need to control during his experiment?
The aim of the experimental model is to test the effect of humidity (changes in weather) on evaporation (rates) from lakes
The control variables in an experiment are the variables that the experimenter intends to keep constant always so as to limit their effect on the measurements of the relationship between the dependent and the independent variable
Therefore in order to have a proper measurement of the effect of humidity on evaporation rate, other variables such as temperature, and the volume of the water in the experiment investigations which affect evaporation rate by the provision of heat, (temperature) and their heat capacity, (the volume and therefore, mass of water) should be controlled
Learn more about controlled variables here;
https://brainly.com/question/2736198
Answer: B: Volume of water and temperature
Explanation:
Just took the quiz
What are the 5 values of the kind organization?
Answer:
I only know 3 of them so hope this help!
Integrity And Ethics. Simply put, the two principles of integrity and ethics translate into doing the right thing, in...
Respect. Without dedicated employees, a company is nothing. ... Committed employees form the backbone of the entire...
Innovation (Not Imitation). This is crucial if a company wants to be a...
IF YOU HAVE TIME COME AND VISIT TO MY CHANNRL IN YOU TUBE IT CALLED: It'z Jennie AMV! THANKS!
1.) Cameron loads a wheelbarrow full of dirt. She then holds up both handles and begins to push it across her yard. The push Cameron uses to move the wheelbarrow is an example of
trajectory
motion
dynamics
force
2.) Jeremy is pushing his two children on a set of swings. He gives his daughter a push and she swings about three feet high. Jeremy gives his son the same push, but he only swings about two feet high. What could account for the difference in how high the kids got?
Jeremy's daughter has more mass, so it takes less force to get her into the air.
Jeremy's son has more mass, so it would take more force to reach the same height as his daughter.
Jeremy's son has less mass, so it would take more force to reach the same height as his daughter.
Jeremy's daughter has more mass, so she accelerates faster than his son.
Answer:
C (Force)
Explanation:
Cmon we should all know dis
Answer:
force and Jeremy's son has more mass
Explanation:
pushing requires force and the son moves less
According to ohms law, as the voltage increases across a 40 ohm resistor what happens to the current, resistors, and resistance
Answer:
As the voltage increases, the current flowing through the circuit increases while the resistance of the resistor remains constant.
Explanation:
Ohm's law states that the current flowing through a circuit is directly proportional to the applied voltage.
V = IR
where;
I is the current
R is the resistance
V is the applied voltage
Based on this law (Ohm's law), as the voltage increases, the current flowing through the circuit increases while the resistance of the resistor remains constant.
Using the solubility curvechoose all of the statements that are correct
Explanation:
where are the statements
__________ is the theory that living things come from other living things.
A.
spontaneous generation
B.
evolution
C.
Darwinism
D.
cell theory
Answer:
A.spontaneous generation
using a diagram explain how acceleration can be obtained from a velocity time graph
Answer:
For any v-t graph the acceleration is the slope of the graph. For average acceleration in a time period ‘t’ consider the change in velocity in time t and divide it by the time t. For instantaneous acceleration you need to go into the realm of differential calculus.
Explanation:
I hope this helps! I would really appreciate it if you would please mark me brainliest! Have a blessed day!
Ayala is making salad dressing. She mixes oil and vinegar in a blender until a smooth consistency is formed. Explain whether this is a heterogeneous or a homogeneous mixture and why
Answer:Hetero
Explanation: Honestly, same as the last guy said
R
R2
R
100 12
300 12
50 12
The question below refers to the circuit shown in the image
9V -
What is the equivalent resistance of the circuit?
O 1500
0 3500
Ο 400Ω
O 4500
Answer:
3500 i would think
Explanation:
A bird flies South for the winter at a constant force of 51 N. Suddenly a wind with a force of 35 N blows due South. What is the net force of the bird?
Answer:
86N
Explanation:
The bird is going south and the wind is also blowing south so all the force is acting in the same direction thus it all adds up.
Describe how the energy is transferred from the gas hob to cook the egg in the water.
Answer:
remember the ways in which the heat is transferred:
Conduction: Heat transfer of two objects touching.
Convection: Heat transfer in a medium with a gradient of temperature.
Radiation: Heat transferred between two objects that not touch each other (an example of this is how the Sun heats up the Earth)
First, we start with the gas itself.
It has a lot of pressure, so when you open the knob, the gas can get out.
The has chemical potential energy.
When you combust the gas, you transform that energy into heat energy, as the flame touches the pot, it starts o also heat the pot.
This heat energy is transferred to the pot, which transfers heat energy to the water by conduction, the heat in the water is "distributed" by convection, and as the water starts to heat up, the energy is transferred to the egg by conduction.
What is the kinetic energy of a 78kg object moving at a velocity of 2.5m/s
Answer:
[tex]\boxed {\boxed {\sf 243.75 \ J }}[/tex]
Explanation:
Kinetic energy is energy an object has due to motion. The formula is:
[tex]KE=\frac {1}{2}mv^2[/tex]
The mass of the object is 78 kilograms and the velocity is 2.5 meters per second.
[tex]m= 78 \ kg \\v= 2.5 \ m/s[/tex]
Substitute the values into the formula.
[tex]KE= \frac {1}{2} (78 \ kg)*(2.5 \ m/s)^2[/tex]
Solve according to PEMDAS: Parentheses, Exponents, Multiplication, Division, Addition, and Subtraction. Solve the exponent first.
(2.5 m/s)²= 2.5 m/s * 2.5 m/s = 6.25 m²/s²[tex]KE= \frac {1}{2}(78 \ kg)*6.25 \ m^2/s^2[/tex]
Multiply all three numbers together.
[tex]KE=39 \ kg * 6.25 \ m^2/s^2\\[/tex]
[tex]KE=243.75 \ kg*m^2/s^2[/tex]
1 kilogram meter squared per second squared is equal to 1 Joule. So, our answer of 243.75 kg *m²/s² is equal to 243.75 Joules.
[tex]KE=243.75 \ J[/tex]
The object has 243.75 Joules of kinetic energy.
The Sun creates energy through a series of steps known as:
The Sun creates energy through a series of steps known as nuclear fusion.
What is nuclear fusion?Nuclear fusion is the process by which atomic nuclei combine to form heavier nuclei, releasing a tremendous amount of energy in the process. In the Sun, this process occurs in the core, where the temperature and pressure are high enough to overcome the electrostatic repulsion between positively charged atomic nuclei. Hydrogen atoms are fused together to form helium atoms, releasing energy in the form of light and heat.
The process of nuclear fusion in the Sun can be broken down into several steps.
The first step involves the collision of two hydrogen atoms to form a deuterium atom, releasing a positron and a neutrino in the process. The deuterium atom can then combine with another hydrogen atom to form helium-3, releasing a gamma ray. Finally, two helium-3 atoms can combine to form helium-4, releasing two protons and releasing even more energy in the process.
Therefore, the process of nuclear fusion in the Sun is a complex series of steps that releases a tremendous amount of energy and is responsible for the light and heat that we receive on Earth.
To learn about Kinetic energy click:
brainly.com/question/26472013
#SPJ2
A negative 6 mC charge enters a region of 45 T magnetic field that is directed up. If the charge is moving toward the south with a speed of 400 m/s
Question: A negative 6 mC charge enters a region of 45 T magnetic field that is directed up. If the charge is moving toward the south with a speed of 400 m/s. determine the magnitude and direction of the force
Answer:
Magitude of F = 108 N
Direction: Perpendicular to the plane containing v and B.
Explanation:
From the question,
Since the velocity of the charge(v), is parallel to the field(B).
Therefore, We apply
F = qvB..................Equation 1
Where F = Force, B = magnetic field, v = velocity, q = Charge.
Given: q = 6 mC = 0.006 C, v = 400 m/s, B = 45 T
Substitute these values into equation 1
F = 0.006×400×45
F = 108 N.
The direction of the force is always perpendicular to the plane containing v and B.
Focus Question: How are physical properties used to compare and classify substances?
Answer:
Properties that can be determined without changing the composition of a substance are referred to as physical properties. Characteristics such as melting point, boiling point, density, solubility, color, odor, etc. ... Physical and chemical properties can be used to classify a substance as ionic or molecular.
Explanation:
Hope it helps! Correct me if I am wrong!
Dont worry im sure about my answer!
If you dont mind can you please mark me as brainlest?
Its ok if you don't want to!
The Earth's atmosphere is opaque to the
part of the electromagnetic
spectrum
a)
b)
c)
-)
)
0
Visible
Infrared
X-Ray
All of the above
A and Care correct
Band C are correct
Your spaceship has run out of fuel and comes to a halt halfway between the earth and the moon. Will you and your spaceship (a combined mass of 5000 kg) fall towards the moon or towards the earth? Show calculations to support your answer.
Answer:
moon
Explanation:
cause yes
During a demonstration of Newton’s laws of motion, a student used the setup shown in Figure 1. The student flicked the index card with a fingertip, and the coin fell straight down into a plastic cup as shown in Figure 2.
A: A falling body accelerates at a constant speed.
B: The motion of an object is constantly changing due to magnetic forces.
C: The force friction causes an object in motion to move faster.
D: An object remains at rest, or at a constant speed, an unbalanced force acts on it.
Answer:
D. An object remains at rest, or at a constant speed, an unbalanced force acts on it.The coin was at rest until the card was removed, so it tended to remain in the same location. Once the card was gone, the unbalanced force of gravity caused the coin to fall.
I hope this helped!+*♡
Un cuerpo cuya masa es de 20 kg se lleva primero a la luna y luego a marte. Teniendo en cuenta el factor que liga masa y peso en marte es de 3,8 N/Kg
Answer:
W = 76 N
Explanation:
In this exercise you are asked to find the weight of the body.
Mass is a quantity that is invariant, it measures the same everywhere, the weight depends on where it is measured, a simple way to find the weight of a body is
W = g m
where g is the constant of the place, in this case we have the weight of the body on Mars and its mass which is constant on Earth and on Mars
W = 3.8 20
W = 76 N
TEST INTRO 20
The fact that a pen drops when you let it go is an example that can help explain ...
A: the hypothesis of gravity.
B: the theory of gravity.
C: the gravity of the situation.
D: the law of gravity:
Answer:
D
Explanation:
answer right away!!—A plucked guitar string emits a dominant
frequency of 320 Hz. What is the
frequency of the 3rd harmonic?
Answer:
20000000000000hz only for this
What will be the change of velocity of a 50kg object if a force of 2,000N
is applied to it for 0.010 seconds?
Answer:
0.4m/s
Explanation:
[tex]F = ma[/tex] where F= force, m= mass, and a=acceleration
we also know that,
a = Δv / t where Δv = change in velocity and t = time
thus F = m ( Δv / t)
[tex]2000=50(\frac{v}{0.01})[/tex]
[tex]\frac{2000}{5000} = v[/tex]
0.4m/s = Δv
Ten examples of artificial luminous objects
paper, pencil, wood, human beings, moon.
Luminous objects are those objects which emit their own light.
Luminous objects can be natural as well as manmade.
One of the examples of natural luminous objects are- torch bulb, stars, sun, lighted candle.
Artificial luminous objects are those which cannot emit their own light.
Some of the examples of the artificial luminous objects are- paper, pencil, wood, human beings, moon.
A scientist is designing a device that will mimic Earth's atmosphere by
blocking high-energy waves from the Sun. Pick three high-energy waves
that the device should be able to block?
Answer:
1. Ultraviolet light (UV)
2. X-rays
3. Gamma-rays
Explanation:
Though there are different types of energy or electromagnetic waves with varying wavelengths, including the likes of Gamma X-rays, ultraviolet light, visible light, infrared radiation, and microwave radiation.
What is more certain is that the atmosphere blocked the high-energy waves from getting to the earth surface or biosphere such as Ultraviolet light (UV), X-rays and Gamma-rays
Which of the following methods transmits a drug directly into the bloodstream?
Answer:
I think Intravenous transmits a drug directly into the bloodstream.
Hope this help! :)
If a fish is trying to capture insect hovering above the surface of water – how will it jump to catch it? Will it aim above or below what it sees? Explain.
Answer:
Above
Explanation:
yes
Covalent compounds......
Covalent compounds are characterized by bonding that involves sharing electrons.
Covalent compounds have the ability to share electrons as they mostly have 4 valence electrons.
What are covalent compounds?
Covalent compounds are defined as type of compounds which are formed by the mutual sharing of electrons to form electron pairs between the two atoms.These electron pairs are called as bonding pairs or shared pair of electrons.
Due to the sharing of valence electrons , the atoms are able to achieve a stable electronic configuration . Covalent compounds have bonding which involves many types of interactions like σ bonding,π bonding ,metal-to-metal bonding ,etc.
Sigma bonds are the strongest covalent bonds while the pi bonds are weaker covalent bonds .Covalent bonds are affected by electronegativities of the atoms present in the molecules.Compounds having covalent bonds have lower melting points as compared to those with ionic bonds.
Learn more about covalent compounds,here:
https://brainly.com/question/21505413
#SPJ2
Please ans fast I will mark brainliest
For sure