Answer:
B
Explanation:
P = I² R
If P is 2 watts and R is 30 ohms:
2 = I² (30)
I = √(1/15)
I ≈ 0.26 A
Answer:
B. 0.26 amps is your answer
What happens to kinetic energy when the speed doubles
Hello There!
Because kinetic energy is proportional to the square of the velocity, when velocity is doubled, kinetic energy is quadrupled.
Obi Wan uses his Jedi mind tricks to compel people to do his will. The words he uses begin in his vocal cords which _____ the air molecules in his throat.
Answer:
The correct missing word is: vibrate.
Explanation:
The words he uses begin in his vocal cords which vibrate the air molecules in his throat.
The process by which the air pressure from the lungs is converted into audible vibrations is known as phonation.
When the air passes through the vocal folds, it causes them to vibrate, as phonation occurs. It is due to the vocal folds that a singer has a wide range of control over the pitch of his voice.
Billy did an investigation to learn whether bean plants will grow if they are given salt water. Billy repeated his experiment three different times. Each time, he used the same kind of been seeds, and he made the salt water by adding exactly 20 grams of salt to 1 liter of water. What is Billy doing by using the same beans and making the salt water exactly the same way each time?
A. using consistency and precision
B. making hypotheses and inferences
C. using safety and observation
D. making predictions and conclusions
B should be your answer good luck!
Answer:
B
Explanation:
THE Answer should be b
1. seesaw
third-class lever
2. pencil sharpener
second-class lever
3. bottle opener
wheel and axle
4. forearm
wedge
5. nail
first-class lever
Answer:
1 seesaw = first class lever
2. pencil and sharpener = wheel and axle
3. bottle opener = second class lever
4. forearm = third class lever
5. nail = wedge
Explanation:
The given objects are classic examples of simple machines.
Lever: There are 3 types of levers and they depend on where the load, applied force, and fulcrum are.
First class levers have the fulcrum in between the load and the applied force. In other words, the load and applied force are at opposite ends. The seesaw is a good example of this. Other examples would be, pliers, scissors, and the like.
Second class levers have the fulcrum and the applied force at the opposite ends. So in this case, the load is found in between. Examples of this would be a bottle opener or a crowbar.
For third class levers, the load and the fulcrum are at opposite ends and the applied force is in between. The forearm is a good example, so is a stapler, or even a broom.
A wedge is another simple machine. It is thick at one end and it gets thinner towards the other end, or it usually has a sharp end. Other examples of this would be an axe, or a knife.
A sharpener is actually a compound machine. The old-fashioned type of pencil sharpener, the one you crank makes use of a wheel and axle and a wedge. A wheel and axle is usually a machine that makes use of two circular parts; a wheel and a rod that is attached to its center.
Final answer:
The list involves identifying simple machines such as lever, wheel and axle, and the wedge. Key corrections include seesaw as a first-class lever, pencil sharpener utilizing wheel and axle, and a nail being a wedge.
Explanation:
The classification of the items listed involves understanding the basic types of simple machines recognized since the Renaissance—lever, wheel and axle, pulley, inclined plane, wedge, and screw. These machines serve as the foundational building blocks to explain how more complicated machines work, offering a mechanical advantage by altering the magnitude or direction of forces. Renaissance scientists identified these six simple machines as crucial in understanding mechanical principles.
A seesaw is an example of a first-class lever, where the fulcrum is between the input force and the load.
A pencil sharpener uses a wheel and axle, which consists of a rod (the axle) fixed to the center of a wheel, simplifying the twisting motion.
A bottle opener typically functions as a second-class lever or sometimes as a lever of another class, depending on its design, where the load is between the fulcrum and the effort.
The forearm acts as a lever within the human body, showcasing how levers are crucial in the design of living organisms for movements such as flexing and extending.
A nail is best described as a wedge, which is essentially two back-to-back inclined planes that apply force over a wider area.
Error corrections in the initial classification include identifying the seesaw as a first-class lever, the bottle opener's potential as a second-class lever depending on its design, the pencil sharpener as involving wheel and axle mechanics, the forearm as a biological example of lever mechanics, and finally, recognizing a nail as a form of wedge, not a lever.
I will mark brainiest!
If your body is wet what is the lowest electrical voltage can be fatal?
A. 100 volts
B. 15 volts
C. 5 volts
D. 10 volts
Applied to the right place in the right way, a 5-volt source can kill a person.
When the human body is wet, its resistance decreases significantly, making it possible for a voltage as low as 10 volts to be fatal. This occurs because the low resistance allows enough current to interfere with heart rhythms. Therefore, the correct answer is 10 volts.
When the human body is wet, its resistance can significantly decrease to approximately 100 ohms. According to Ohm's law, the amount of current (I) that flows through a person depends on the voltage (V) and the resistance (R). For a fatal current, even a small voltage can become dangerous. Generally, it is considered that as little as 10 volts can be fatal as it may drive a current that interferes with heart rhythms. Therefore, the correct answer is 10 volts.
Calculate the orbital radius of the hydrogen atom for the first principal quantum number. Use the general expression given in the test to calculate this value. (Hint: Quantum numbers are not significant digits and should not be counted as such in determining your final answer. Thus, this answer should have 2 significant digits.)
1.1
0.53
5.3
Answer:
5.3 A
Explanation:
The orbital radius for the generic nth-level in the hydrogen atom is given by
[tex]a_n = n^2 a_0[/tex]
where:
[tex]a_0 = \frac{\epsilon_0 h^2}{\pi m_e e^2}[/tex]
is the Bohr radius, with
[tex]\epsilon_0 = 8.85\cdot 10^{-12} F/m[/tex] being the vacuum permittivity
[tex]h=6.63\cdot 10^{-34}Js[/tex] is the Planck constant
[tex]m_e = 9.11\cdot 10^{-31} kg[/tex] is the electron mass
[tex]e=1.6\cdot 10^{-19} C[/tex] is the electron charge
Substituting all this numbers into the formula, we find
[tex]a_0 = 5.3\cdot 10^{-10} m = 5.3 A[/tex]
and since
n = 1
the radius of the hydrogen atom for the first principal quantum number is
[tex]a_1 = 1^2 a_0 = 1 \cdot (5.3 A)=5.3 A[/tex]
Answer:
0.53 A
Explanation:
Identify one organism in the chart that is a decomposer
Answer: Most decomposers are microscopic organisms, including protozoa and bacteria. Other decomposers are big enough to see without a microscope. They include fungi along with invertebrate organisms sometimes called detritivores, which include earthworms, termites, and millipedes.
Explanation:
Lithium atoms give electrons to bromine atoms to form
Lithium atoms give electrons to bromine atoms to form ionic bond.
What is ionic bond?Lithium (Li) is the 3rd element in the periodic table. It can chemically combine with the Bromine (Br) element to form a chemical compound called Lithium bromide.
The Lithium Bromide compound is formed by lithium and bromine is an ionic compound. The bond formed between lithium and bromine is due to the transfer of electrons.
Thus, the Lithium atoms give electrons to bromine atoms to form ionic bond.
Learn more about ionic bond.
https://brainly.com/question/11527546
#SPJ2
Is carbon a metal, nonmetal, or semi-metal
Answer: Non metal.
Explanation: Carbon has 4 electrons in it’s valence shell which makes it a metalloid but commonly it is considered as a non metal.
Carbon is considered a nonmetal due to its brittleness, dull appearance, and inability to be reshaped into sheets or wires, despite being a good conductor of heat and electricity.
Explanation:Is Carbon a Metal, Nonmetal, or Semi-Metal?
Carbon is classified as a nonmetal. It is a black and brittle substance that is a good conductor of electricity and heat, which might seem like metallic properties. However, unlike metals, carbon cannot be made into sheets or wires because it is not malleable or ductile. In fact, carbon exhibits several nonmetallic properties such as being dull and brittle. When examining the periodic table, nonmetals are located in the upper right corner except for hydrogen, which is why carbon firmly fits within the nonmetal classification.
In contrast, metals are typically shiny, silvery, and excellent conductors of heat and electricity, plus they can be shaped into sheets (malleable) or wires (ductile). Semi-metals or metalloids exhibit properties that are intermediate between metals and nonmetals. These elements are found along a diagonal band on the periodic table. Therefore, based on its properties and location on the periodic table, carbon is considered a nonmetal.
Conduction stops when all substances have
Answer:-
It stops when the temperature of all the particles/atoms is equal.
Explanation:
When two objects or substances that have different temperature are placed in contact with each other then there will be flow of heat from hotter object to colder object.
This transfer of heat will continue until the temperature of both the objects become equal.
For example, if a metal box has [tex]T_{1}[/tex] temperature that is higher than another metal box adjacent to it which has [tex]T_{2}[/tex] temperature. Then heat will flow from [tex]T_{1}[/tex] to [tex]T_{2}[/tex] until the temperature of both the boxes become equal to [tex]T_{3}[/tex].
Hence, we can conclude that conduction stops when all substances have same temperature.
A substance has a specific heat of point 870JGC it requires 2000.0 J to increase the temperature of the 10 g of the substance from its original temperature to it's final temperature by how many degrees did the substance increase
Answer:
[tex]229.9^{\circ} C[/tex]
Explanation:
The increase in temperature of a substance is given by
[tex]\Delta T = \frac{Q}{m C_s}[/tex]
where
Q is the amount of heat absorbed by the substance
m is the mass of the substance
Cs is the specific heat capacity
In this problem,
Q = 2000.0 J
m = 10 g
Cs = 0.870 J/gC
Substituting, we find the increase in temperature:
[tex]\Delta T = \frac{2000.0 J}{(10 g)(0.870 g/JC)}=229.9^{\circ} C[/tex]
What is the initial upward velocity of a projectile fired at an angle of 40 m/s at an angle of 20o? A) 2 m/s B) 13.68 m/s C) 14.55 m/s D) 38 m/s
Find the upward velocityt by multiplying the speed by the cos of the angle.
= 40 x cos(20) = 37.588 m/s
Round to 38 m/s
The answer is D.
Answer: I choose A
Explanation:
Which of the following statements regarding the moon and Earth is correct?
A. Earth and the moon are nearly the same age.
B. Earth and the moon have nearly the same mass.
C. Earth is tidally locked, while the moon spins on its axis.
D. The moon is older than Earth by approximately 300 million years.
Answer: Option 'D' is correct.
Explanation:
Earth has one natural satellite i.e. "Moon".
Earth spins on its axis due to moon is tidally locked.
The mass of moon is much greater than the mass of earth.
The age of moon is much older than the age of Earth.
The moon is older than Earth by approximately 300 million years.
so, only one statement is correct i.e. 'D'.
Hence, Option 'D' is correct.
Answer:
TOOK THE TEST AND GOT IT WRONG! D IS NOT THE ANSWER!!
Explanation:
Hope this helps! have a good day!
What effect does solar radiation have on climate when comparing the equator to polar- regions?
Answer:
The solar radiation is one of the main factors that shapes the climate all over the globe, so the climate differs with the less or more solar radiation it gets. The polar regions are cold, this is due to the fact that the solar radiation in here is very obscure, because the solar radiation falls at a very wide angle the heat is dispersed over larger area, thus the land gets very little warmth. The Equator, on the other hand, gets direct solar radiation, the sun light falls at a 90 degrees angle or close to it, so the radiation is more concentrated on a smaller area, thus the warming is bigger.
* hopefully this helps:) Mark me the brainliest:)!!!
Final answer:
Solar radiation impacts the equator and polar regions differently; the equator receives more direct sunlight, resulting in higher temperatures and less seasonal variation, while the polar regions receive oblique rays that lead to less intense solar radiation and increased seasonal temperature extremes. The Earth's oceans and atmosphere redistribute heat, and the tilt of the Earth contributes to seasonal differences in climate.
Explanation:
The solar radiation affects the climate differently at the equator compared to the polar regions due to the Earth's curvature and tilt. Near the equator, solar radiation is more direct, leading to higher temperatures and more consistent climatic conditions throughout the year. In contrast, polar regions receive oblique rays, resulting in less intense solar radiation and more extreme seasonal variations in temperature.
Oceans and the atmosphere work together to redistribute this heat, moderating climates by transferring warmth from equatorial regions to the poles. This is facilitated by ocean currents and atmospheric circulation, which move heat laterally across the planet, bringing about a more balanced climate globally. The presence of ice and snow in polar regions, with high albedo, reflects significant amounts of solar radiation, further reducing the energy absorbed in these areas.
Throughout the year, solar radiation varies based on latitude, with regions between 23.5 degrees north and south experiencing the highest amounts of solar radiation during the equinoxes. The changing angles of solar radiation due to the Earth's tilt contribute to seasonal differences, with more direct sunlight during summer months leading to warmer temperatures and an increased angle during winter causing more reflected sunlight and cooler temperatures.
A person walks 2 miles every day to work, leaving her front porch at 7:00 A.M. and arriving at work at 7:30 A.M. ON the way home she walks the same route and ends at her front porch. What is her displacement?
Answer:
The displacement is zero miles
Explanation:
The displacement of an object that moves from point A to point B is defined as
[tex]d =B-A[/tex]
Where d is the displacement of the object. The displacement does not depend on the trajectory of the object. It only depends on the linear distance between the end point and the starting point.
In this case we know that the person walks from home to work and then walks from work to home. Therefore, the total displacement is the linear distance between the point where its journey begins and the point where the route ends.
The tour begins on the front porch of your house and ends on the front porch of your house (when you return from work). If we call A to the front porch of the house then the displacement is:
[tex]d = A-A = 0[/tex]
The displacement is zero miles, since the person finishes the journey just where it started (front porch)
Maya tried to hit four golf balls into a hole marked with a flag. The diagram shows where the golf balls landed.
Answer:
Explanation: high precision, high accuracy, how did i get it well the golf balls were not accurate but the precision of the balls were all in one place.
Answer:
High precison, low accuracy
Explanation:
Please I need help on this one
Answer:
Your answer would be A, Ball A had more kinetic energy than Ball B.
Explanation:
This is the correct answer because kinetic energy is motion. If balls A and B have an equal mass, but ball A reaches the end of the lane quicker, this is the only answer that is possible.
Which best describes accuracy?
A.) the smallness of the graduations on a measuring tool
B.) the reproducibility of a measured value
C.) the dependence of a measured value on a controlled value
D.) the agreement between a measured value and an accepted value
Answer: A.) the smallness of the graduations on a measuring tool
Explanation:
Accuracy is defined as the closeness of the measured value to the actual value. Therefore, out of the options, this is best described by A. the smallness of the graduations on a measuring tool. This is because smaller graduations mean that the value can be measured to a smaller level, making it more accurate. PLEASE GIVE ME BRAINIEST
An airplane flies 525 kilometers north in 1.25 hours. What is the airplane's velocity?
Speed = (distance covered) / (time to cover the distance)
Speed = (525 km) / (1.25 hrs)
Speed = (525/1.25) km/hr
Speed = 420 km/hr
Velocity = speed and the direction from start to finish
Velocity = 420 km/hr North
Velocity of a object is the ratio of distance covered by the object to the time taken by it. The velocity of the airplane is 420 kilometre per hours.
Given information-
The total distance covered by the airplane in north direction is 525 kilometres.
The total time taken by the airplane to cover this distance is 1.25 hours.
What is velocity?Velocity of a object is the ratio of distance covered by the object to the time taken by it.
It can be given as,
[tex]v=\dfrac{x}{t}[/tex]
Here, [tex]x[/tex] is the distance covered by the object and [tex]t[/tex] is time taken by it.
As he total distance covered by the airplane in north direction is 525 kilometres and the total time taken by the airplane to cover this distance is 1.25 hours.
Thus the velocity of the body can be given as,
[tex]v=\dfrac{525}{1.25}\\v=420[/tex]
Hence the velocity of the airplane is 420 kilometre per hours.
Learn more about the velocity here;
https://brainly.com/question/862972
7. A force of 100 N acting on a body gives it a speed of 200 m/s in 2
sec. what is the mass of the body?
a. 1kg
b. 5 kg
c. 10kg
d. 15kg
Answer:
Choice a. 1 kg, assuming that all other forces on the object (if any) are balanced.
Explanation:
By Newton's Second Law,
[tex]\displaystyle a = \frac{\Sigma F}{m}[/tex],
where
[tex]a[/tex] is the acceleration of the object in [tex]\text{m}\cdot\text{s}^{-2}[/tex],[tex]\Sigma F[/tex] is the net force on the object in Newtons, and[tex]m[/tex] is the mass of the object in kilograms.As a result,
[tex]\displaystyle m = \frac{\Sigma F}{a}[/tex].
Assume that all other forces on this object are balanced. The net force on the object will be [tex]100\;\text{N}[/tex]. The net force is constant. Acceleration should also be constant and the same as the average acceleration in the two seconds.
What is the average acceleration of this object?[tex]\displaystyle \begin{aligned}\text{Acceleration} &= \text{Average Acceleration}=\frac{\text{Change in Velocity}}{\text{Time Taken}}\end{aligned}[/tex].
[tex]\displaystyle {a} = \frac{200\;\text{m}\cdot\text{s}^{-1}}{2\;\text{s}}=100\;\text{m}\cdot\text{s}^{-2}[/tex].
Apply Newton's Second Law to find the mass of the object.[tex]\displaystyle m = \frac{\Sigma F}{a} = \frac{100\;\text{N}}{100\;\text{m}\cdot\text{s}^{-2}} = 1\;\text{kg}[/tex].
Answer:
a.1kg
Explanation:
Which describes an object in projectile motion? Check all that apply.
Gravity acts to pull the object down.
The object moves in a straight path.
The forward velocity of the object is 0 m/s.
The object’s inertia carries it forward.
The path of the object is curved.
Please and Thank You!
Answer:
Gravity acts to pull the object down.
The object’s inertia carries it forward.
The path of the object is curved.
Explanation:
The motion of a projectile consists of two separate motions:
- A uniform motion along the horizontal direction, where the velocity is constant; since there are no forces along this direction, the velocity does not change, and so the object continues its motion for inertia --> so, the statement "The object’s inertia carries it forward" is true.
- A uniformly accelerated motion along the vertical direction, with a constant downward acceleration (g=9.8 m/s^2, acceleration due to gravity). So, the vertical velocity changes, due to the presence of the gravity that acts to pull the object down.
- As a result of the combination of these two motions, the object follows a curved path (in particular, it is a parabolic path).
A stone is projected from the ground with a velocity 14m/s one second later it clears a wall 2 m high. The angle of projection is?
A stone is projected from the ground with a velocity 14 m/sec one second later it clears 2 meter walls then angle of projection is 30 degree.
14sinθ×1−5×12=25
14sin=30
sin=30/14
sinθ>2 not possible
vsinθt−1/2×gt^2=2
14×sinθ−5=2
14xsinθ=7
Sinθ=7/14
Sinθ=1/2
θ=30 degree
What is projectile motion?
Projectile motion is a type of motion in which a object is thrown from the surface earth at some angle it will take projectile projection .
In above question a man thrown a object 14 m/sec an it will moves 2 meter.
Then
vsinθ×t−1/2×gt^2=25
where v = intial velocity in m/sec
t = time in sec
g = acceleration due to gravity
14sinθ×1−5×12=25
14sin=30
sin=30/14
sinθ>2 not possible
vsinθt−1/2×gt^2=2
14×sinθ−5=2
14xsinθ=7
Sinθ=7/14
Sinθ=1/2
θ=30 degree
Therefore, A stone is projected from the ground with a velocity 14 m/sec one second later it clears 2 meter walls then angle of projection is 30 degree.
Learn more about projectile motion here:
https://brainly.com/question/11515753
#SPJ6
1)
What is a column called in the periodic table and what do the elements in each column have in common?
A) period; the same atomic mass
B) group; the same number of electrons
C) period; the same number of atomic orbitals
D) group; the same number of valence electrons
2)
The alkali metals, found in group 1 of the periodic table, are very reactive metals that do not occur freely in nature. These metals have only one electron in their outer shell. Therefore, they readily lose that one electron to form ionic bonds with other elements. Sodium (Na) is an alkali metal that bonds with Chlorine (Cl), a halogen, to form table salt (NaCl). Based on what the periodic table can tell you about these two elements, explain how and why they bond to form NaCl.
A) Na and Cl share electrons to form an ionic bond.
B) Na and Cl share electrons to form a covalent bond.
C) Na and Cl transfer electrons to form ions and create an ionic bond.
D) Na and Cl transfer electrons to form ions and create a covalent bond.
Answer:
1. D) group; the same number of valence electrons
A group is a column in the periodic table where elements have the same number of valence electrons. Sodium and Chlorine bond to form table salt through an ionic bond.
Explanation:A column in the periodic table is called a group. Elements in each group have the same number of valence electrons. This means that they have similar chemical properties and tend to react in similar ways.
Sodium (Na) and Chlorine (Cl) bond to form table salt (NaCl) through an ionic bond. Na transfers an electron to Cl, resulting in the formation of Na+ and Cl- ions. The opposite charges of the ions attract each other, creating the ionic bond in NaCl.
Learn more about Periodic table here:https://brainly.com/question/35461104
#SPJ2
Calculate the work done to stretch an elastic string by 40cm if a force of 10N produces an extension of 4cm in it?
Answer:
40 J
Explanation:
Work = change in energy
W = 1/2 k (Δx)²
First we need to find the value of k.
F = kΔx
10 N = k (0.04 m)
k = 250 N/m
Solving for work
W = (250 N/m) (0.40 m)²
W = 40 J
Study the image. Which phase of the moon as shown? Full moon, first quarter, waning gibbous, waxing crescent
-- If you're observing the moon from a location in the northern hemisphere, like Canada, Russia, the US, or Israel, then it looks like this picture during the waxing crescent phase.
-- If you're observing the moon from a location in the southern hemisphere, like Australia, South Africa, Paraguay, or Antarctica, then it looks like this picture during the waning crescent phase.
Answer:
D. waxing crescent.
Explanation:
So first off its definetly not a full moon because its not full. Not a first quarter because a first quarter is away from the sun on the side of the earth. and not a waning gibbous because only a waxing crescent would be like the one shown on the picture so therefore, its D
Imagine you are digging a hole to the center of the earth. In which order would dig through them?
A. inner core, outer core, upper mantle, lower mantle, crust
B. crust, upper mantle, lower mantle, outer core, inner core
C. crust, outer core, inner core, upper mantle, lower mantle
D. inner core, outer core, lower mantle, upper mantle, crust
Answer:
Crust, Upper Mantle, Lower Mantle, Outer Core, Inner Core
Explanation:
HELP!!!
Which of these would be supported by the graph?
Answer:
C
Explanation:
It is the answer
Answer:
C. KBr is about twice as soluble as NaCl at 60°C
Explanation:
From the graph of solubility of various solutes with respect to temperature we can figure-out that on y-axis we have the increasing solubility of the solvents in gram per 100 gram of water as we move upwards and on x-axis we have increasing temperature of the solvent (water) moving rightwards.
As we move vertically up through 60°C line we notice that NaCl has solubility nearly 40 grams per 100 gram of water whereas on further moving up in the same line we find that KBr has nearly 80 gram per 100 gram of solubility.
The solubility of NaCl varies negligibly with change in the temperature of water whereas the solubility of KNO3 is greatly increased by the increasing temperature.
Solid solutes have a tendency to dissolve highly in the water with increase in temperature because of increased inter molecular space of the solvent molecules on heating and loosening of the bonds of solid solute.But in case of a gaseous solute the tendency to dissolve into water decreases with increase in temperature because here if the kinetic energy of the molecules increases for the solute then its molecules will escape from the solvent.The duckbill platypus and spiny anteater are the only two known
marsupials.
a. true
b. false
Answer:
I believe it is False.
Explanation:
Hope my answer has helped you!
If the mass of an object on earth is 100 kg what is it’s weigjt in earth
W = 980N. The weight of an object of 100Kg in the Earth is 980N.
The weight is a measure of the gravitational force acting on an object, the weight is equivalent to the force exerted by a body on a point of support, caused by the action of the local gravitational field on the mass of the body.
it can be defined as the product of mass by the acceleration of gravity, w = mg. Since weight is a force, its unit is the Newton N.
If the mass of an object on earth is 100 kg, then is weight is:
W = (100Kg)(9.8m/s²) = 980N.
What change of state occurs during vaporization?
Answer:
Liquid to gas
Explanation:
When molecules are in the liquid state, they are held together by internal forces of the molecules while moving in a constant motion.Increasing the temperature through heating, will make the molecules move faster and collide at a higher rate because they gain kinetic energy after obtaining the heat.This will loosen the forces holding the molecules together leading to vaporazation.