Answer:
Focal length, f = 10 cm
Explanation:
We have,
A concave mirror forms a real image at 15.0 cm from the mirror surface along the principal axis, it means that the image distance is 15 cm
The object is placed at a distance of 30 cm, u = -30 cm
It is required to find the focal length of the mirror. Let it is f. Using mirror's formula to find it:
[tex]\dfrac{1}{v}-\dfrac{1}{u}=\dfrac{1}{f}\\\\\dfrac{1}{15}-\dfrac{1}{(-30)}=\dfrac{1}{f}\\\\f=10\ cm[/tex]
So, the focal length of the mirror is 10 cm.
75 points!
In a particular chemical reaction, the energy of the reactants is 30 kJ and the energy of the products is 5 kJ. The maximum energy of the system is 40 kJ.
A. Sketch a potential energy diagram for this reaction. Make sure to label the energy of the reactants, the energy of the products, the activation energy, and the enthalpy change for the reaction.
B. What is the activation energy for this reaction?
C. What is the enthalpy change for this reaction?
D. Is this reaction endothermic or exothermic? Explain your answer in two ways: first, using the energy values, and second, by referring to the shape of the graph.
Answer:
The activation energy of a chemical reaction is the energy require to form the activated complex and the activated complex then converted to product. The activation energy is always positive for both endothermic and exothermic reactions.
Explanation:
pls if im worng add a star pls
The two major problems with most motor vehicles are that they burn fossil fuels and _____________.
A. Create radioactive waste
B. Create thermal pollution
C. Release chlorofluorocarbons
D. Release greenhouse gases
Answer:
The two major problems with most motor vehicles are that they burn fossil fuels and. Release greenhouse gases ( D)
The two major problems with most motor vehicles are that they burn fossil fuels and release greenhouse gases. Option (D) is correct answer.
What are the greenhouse gases?The Earth's atmosphere naturally contains these gases or compounds. But humans are also responsible for their release. These gases are essential for capturing the heat from the Sun and gradually raising Earth's temperature. Because of the balance between the energy it absorbs and the energy it reflects back into space, the Earth is habitable for people.
The greenhouse effect is the term used to describe how the greenhouse gases in the atmosphere capture and emit radiation. Without this mechanism, Earth would either be extremely cool or extremely hot, which would make life on the planet impossible.
The greenhouse effect occurs naturally. The release of industrial gases into the atmosphere, the burning of fossil fuels, and other improper human activity are all contributing to an increase in greenhouse gas emissions.
As a result, this has contributed to global warming.
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How does planting high yield crop varieties make farming more sustainable
Answer:
The more high yield crops are planted, the more production there will be from plants.
Explanation:
High-yield plants are plants that are genetically modified or modified artificially in a way that makes farming plants more efficient. More crops grow, therefore more money.
The answer is, the more high-yield plants there are, the more efficiency there will be from farming.
Answer:
Its D
Explanation:
my options were these
A. It increases the amount of water needed
B. It keeps soil fertility from diminishing over time
C. It keeps chemicals form entering the watershed
D. It decreases the amount of land needed
HELP ASAP
this is for science, and if i get the questions right, I pass, but the teacher never taught us the lesson, idrk y. so i really need help:( Im giving away 20 points so please give me your best answers ;)
1. As an astronaut travels from the surface of Earth to a position that is four times as far away from the center of Earth, based on the Law of Gravity which of the following statement is true?
a. mass remains the same and the gravitational pull from Earth decreases
b. weight remains the same and the gravitational pull from Earth changes
c. weight increases and the gravitational pull from Earth stays the same
d. mass decreases and the gravitational pull from Earth increases
2. A satellite is sent into orbit around the Earth, In which of the following situation would the gravitational force be the greatest?
A. 1200 lb satellite orbiting 150 miles above Earth’s surface
b. 850 lb satellite orbiting 150 miles above Earth’s surface
c. 850 lb satellite orbiting 1500 miles above Earth’s surface
d. 1200 lb satellite orbiting 1500 miles above Earth’s surface
3. High and low tides are the regular pattern of rising and sinking ocean-water levels. They are caused when the sun’s gravity and the moon’s gravity pull on ocean water. The moon’s gravity has a greater effect on Earth’s oceans than the sun’s gravity. Why would the moon have a greater effect than the sun?
a. The moon has less mass than the sun.
b. The moon is closer to Earth than the sun.
c. The moon is not as hot as the sun.
d. The moon has less mass than Earth.
4. Which statement about the universality of gravity is false?
a. The gravitational force between two objects depends only on their masses.
b. Any two objects that have mass also have a force of gravity acting between them, no matter how far apart they are.
c. The gravitational force between two objects increases if the objects move closer together.
d. The gravitational force between two objects increases if mass is added to one object.
Answer:
1)a- mass never changes as you move from the earth
2)actually am not sure I haven't been taught that too
3)b
4)a-it doesn't depend only on mass but also weight
The pressure of water at the bottom of a well is _________ than at the surface of the pond.
Answer:
Greater
Explanation:
When you go deeper in water, the presure increases, the deeper you go, so it would be greater in a well then the surfce of a pond. Hope this helps!
What is the volume of this rectangular prism?
1/4cm 1/3cm 1/2cm
Answer:
1/24
Explanation:
1/4 * 1/3 * 1/2 = 1/24
Answer:
1/24
Explanation:
Which of the following gives the best description of the motion of electrons in a conductor?
A.
The electrons in conductors usually move in straight lines.
B.
The electrons in conductors are able to move about freely.
C.
The electrons in insulators are unable to move about freely.
D.
The electrons in conductors usually move in regular patterns.
Answer:
The correct answer is B. The electrons in conductors are able to move about freely.
Explanation:
The conductive materials are those that have an atomic structure that favors that the electrical charges can be easily moved inside. That is, a conductive material is one that allows the transport of electric charge, presenting little resistance to the movement of electric charge or electrons when an electric field is applied.
The arrangement and freedom of movement of the electrons along the atomic structure is what favors the circulation of electricity through the conductor.
So, the correct answer is B. The electrons in conductors are able to move about freely.
Which of the following describes how the current in a circuit can be increased? Select all that apply.
A.
increase the voltage and the resistance
B.
increase the voltage while keeping the resistance constant
C.
decrease the voltage and the resistance
D.
decrease the resistance while keeping the voltage constant
Answer:
B. and D. would be my best guess.
Explanation:
The reason why is because if you lower the resistance, the voltage will be higher, and if you higher the voltage, the resistance would be lower and the voltage would higher.
does space have plenty of oxygen
Answer:
I don't think so because we can't breathe in space
Explanation:
Answer:
No
Explanation:
There is no oxygen in space, so astronauts must bring tanks of oxygen
how does the electric force between two charged particles change if the distance between them is increased by a factor of 3? a. it is reduced by a factor of 3 b. it is increased by a factor of 3 c. it is increased by a factor of 9 d. it is decreased by a factor of 9
Answer:
It is reduced by a factor of 9
Signals that are broken up into binary code are characterized as
Well I have 2 examples.
AM/FM radio is a perfect type of technology.
A smart phone is also a great presentation of technology.
Answer:Continuous signals
A loop with a break in it that prevents current from flowing is called a(n)_______
circuit.
Answer:
an open circuit
Explanation:
Which statement correctly describes the differences between positive and negative acceleration?
Positive acceleration describes a change in speed: negative acceleration describes no change in speed.
Positive acceleration describes no change in speed; negative acceleration describes a change in speed.
Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.
Positive acceleration describes a decrease in speed negative acceleration describes an increase in speed.
Answer: positive accel.=increase in speed
negative accel.= decrease in speed
Explanation:
A uniform electric field contains a number of particles. All are experiencing forces in the same direction as the electric field. What can be concluded from this?
All the particles have negative charges.
All the particles have positive charges.
All the particles are charged, but they may be positive or negative.
All the particles must be uncharged.
Answer: D
All the particles must be uncharged
Explanation:
If all the particles are positively charged, then there will be force of repulsion between them which will give different directions away from each other. The same is applicable if they are all negatively charged.
If the particles are positively and negatively charged, their will be force of attraction between them which will give different directions towards each other.
For all to be experiencing forces in the same direction, We can conclude that
All the particles must be uncharged.
Answer:
This picture represents the electric field diagram between two particles with static charges.
Do the two particles have the same charge?
✔ no
If the particles are free to move, what affect will the two particles have on each other?
✔ They will attract each other.
If a third particle was added to this field with a positive charge, what would it be attracted to?
✔ B
If an uncharged particle was placed between A and B, which way would it move?
✔ neither direction
Explanation:
Two chickens are bred and produce the following numbers of offspring. What are the most likely appearances of the parents?
Table of offspring
A. Both parents have red/white feathers.
B. Both parents have white feathers.
C. One parent has white feathers, and one parent has red/white feathers.
D. One parent has white feathers, and one parent has red feathers.
Answer:
Well, Your best answer will be is C. One parent has white feathers, and one parent has red/white feathers.
GOOD LUCK!~
[tex]^{By[/tex][tex]^{Itsbrazts[/tex]
Answer:
c
Explanation:
Determining Charge
An element becomes a positively charged ion when it
oloses protons.
loses electrons.
gains electrons
gains neutrons.
Answer:
hey friend,
an element becomes a positively charged ion when it loses electrons
Please help! I will give Brainliest! The image shows a cross section of a landscape and a well.
1: Land surface. 2: Unsaturated zone. 3: Groundwater. 4: Saturated zone.
Please Hurry timed test! Which of the layers shown is an aquifer?
1
2
3
4
Answer:
3!
Explanation:
have a nice day
Which phrase correctly describes ice?
A) Rigid and having low viscosity
B) Crystalline and having high surface tension
C) Amorphous and having low viscosity
D) Crystalline and rigid
Answer: D) Crystalline and rigid
Explanation:
Ice is considered to be a rigid mineral. It possesses a regular crystalline structure based on the molecule of water, which consists of a single oxygen atom covalently bonded to two hydrogen atoms, or H–O–H.
Answer: D
Explanation:
Traveling in circle requires a net force
Answer:
Circular motion requires a net inward or "centripetal" force. Without a net centripetal force, an object cannot travel in circular motion. In fact, if the forces are balanced, then an object in motion continues in motion in a straight line at constant speed.
Explanation:
Which is NOT a subjective feeling experience? A) Happy B) Sore C) Angry D) Sad
Answer:
b sore
Explanation:
because it's a physical feeling I think
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Balance chemical reactions: please help question attached
Each antibody can recognize how many types of invaders of the body? A. 1 B. 10 C. 100 D. 1,000
Answer: D. 1,000
Explanation:
The antibodies are special proteins which can detect the foreign antigens in the body of the host and fight against these antigens. This way the antibodies prevent the infection in the body.
There are five different classes of antibodies in the human body these are IgA, IgG, IgM, IgE and IgD. Each antibody can recognize more than 1,000 antigens of foreign pathogens.
the two ways you could increase acceleration
Answer: mass(how much the object weighs) and force(how hard you push the object)
Explanation:
For each of the following solutions, name the solvent and the solute
Saltater
Seltzer water
Lemonade made from powdered drink mix
Answer:
Explanation:
The solvent in all the given solutions is water. The solute in the salt water is salt and the solute in the seltzer water or carbonated water is carbon dioxide. The solute in lemonade is lemon pulp juice.
What is a solution?A solution is the combination of a solute and a solvent. The solute can be of completely soluble , partially soluble or insoluble in the solvent. The completely dissolving solute forms a homogeneous solution.
A partially soluble or insoluble solution solutes form heterogeneous solutions. The solubility depends on the bond type, mass, pressure, temperature etc.
The solution salt water is formed by dissolving salt in the solvent, water. Similarly, the seltzer water or carbonated water is formed by carbon dioxide dissolved in water solvent.The solute in lemonade is lemon juice and solvent is water.
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What is the net force acting on a .15 kg hockey puck accelerating at a rate of 12 m/s2
Answer:
The net force is 1.8N
Explanation:
Given that the formula for force is Force = mass×acceleration. So you have to substitute the values into the formula :
[tex]force = mass \times acceleration[/tex]
Let mass = 0.15kg,
Let acceleration = 12m/s²,
[tex]force = 0.15 \times 12[/tex]
[tex]force = 1.8[/tex]
Answer:
1.8 Newtons
Explanation:
We want to figure out the net force acting on a 0.15 kg hockey puck that has an acceleration of 12 m/s². To solve this, we must apply Newton's Second Law of Motion which is denoted by the formula: f = ma.
Here, f is the force, m is the mass, and a is the acceleration. Plug our given values in to find f:
f = ma
f = (0.15 kg) * (12 m/s²) = 1.8 Newtons
Thus, the answer is 1.8 N.
~ an aesthetics lover
2. What other physical quantity might be more important to weightlifters than
how much actual work they do?
Answer:
The pressure on their bone
Center of mass & balance.
David drinks a glass of water in his kitchen. The water is at room temperature, and David
decides to make it colder by adding ice. Which of the following describes why the ice cubes
will melt?
A. Liquid water is reacting with solid water to absorb energy.
B. Water is evaporating from the surface of the water.
C. Slow-moving molecules move out of the ice.
D. Heat from the water moves into the ice.
Answer:
I think it's C
Explanation:
Which term is defined as the force applied to the object divided by the mass of the object?
speed
velocity
mass
acceleration
Answer:
acceleration
Explanation:
From the question: "FORCE... divided by the MASS..." is translated to a math equation as "F / m", where "F" is the force and "m" is the mass.
Now, the second Newton's law says "F = m . a ", where a is acceleration.
If you move m to the left side, clearly you have "F / m", and "a" is alone to the right. Math equation:
a = F / m
acceleration = force / mass
An airplane moves in straight level flight at constant velocity. What is the
net force acting on it if the mass of the plane is 1000 kg and the frictional
drag of the air is 1800 N? *
Answer:
Net force = 0
Explanation:
We have, an airplane moves in straight level flight at constant velocity.
Mass of the plane is 1000 kg
The frictional force acting of the air is 1800 N.
It is required to find the net force acting on it. We know that net force is given by the product of mass and acceleration. But here the airplane moves with constant speed, it means its acceleration is equal to 0 such that net force is equal to 0.
