Which option is an example of a pure substance?
A. The compound strontium oxide
B. Carbon atoms spread evenly throughout iron atoms
C. A vinegar and oil salad dressing
D. A disc of silicon with stones of germanium in it
GIVING BRAINLIEST PLEASE HELP!!
-if you answer correctly ill give you brainliest which will give you 25pts-
Answer:
b and d :)
Explanation:
Answer:
A, B, And C,
Explanation:
The law of conservation of energy is a physical law that states energy cannot be created or destroyed but may be changed from one form to another. Another way of stating this law of chemistry is to say the total energy of an isolated system remains constant or is conserved within a given frame of reference.
It took 3.5 hours for a train to travel the distance between two cities at a velocity of 120 km/h. How far did the train travel between the two cities?
Answer: 420 km
Explanation:
120 per hour, 3.5 hours
120 x 3.5 = 420
PWEESE HELPPPP I'LL GIVE BRAINLIEST, (NO LINKS OR I'LL REPORT)
（︶^︶）
A sound wave is made of a series of compressions and
a.
extensions.
c.
rarefactions.
b.
volumes.
d.
refractions.
Answer:
extensions.
Explanation:
Hope this helps
Answer:
extensions i think because sound waves travel through the air and to our ears so its extended
Explanation:
Help please:A boy weighing 30 kg rides a scooter. The total kinetic energy of the boy and the scooter is 437.6 J. Determine the speed at which the boy moves if the mass of the scooter is 5kg?
Answer:
5 m/s
Explanation:
Mass of the boy + scooter system = 35 kg
Kinetic Energy = 437.6 J
437.6 = [tex]\frac{1}{2} 35 {v}^2[/tex]
25.0057143 = [tex]v^{2}[/tex]
v = 5 m/s
I'm stuck between B and C
In the problem, I know the potential energy increases because the height increases.
A block is at the bottom of a frictionless ramp and is given a kick so that it has some initial velocity and starts to slide up the ramp. There
is no air resistance. Which of the following is true of the energy of the block as it slides?
(A) Its potential energy will increase; its kinetic energy will decrease.
(C) Both its potential and kinetic energies will increase.
(B) Its potential energy will decrease; its kinetic energy will increase.
(D) Both its potential and kinetic energies will decrease.
Answer:
Explanation:
The answer is A. First of all, due to the First Law of Thermodynamics, energy cannot be created or destroyed, it only changes form. That being said, it is impossible for the PE and the KE to both increase or decrease at the same time. The second one starts decreasing, the other starts increasing at the exact same rate. PE exists or is at its highest when an object has the potential to fall to a point lower than it is, and it is at this point where Kinetic energy is the lowest. If this block is kicked UP a ramp, which is odd but there you have it, the potential energy increases as it gets higher off the ground. Because of gravity, and assuming that once the block is kicked, the foot that kicked it is no longer important to it (meaning it's not being pushed up, it's just kicked once and that's it) and it will slow down very quickly. KE exists where there is a great amount of velocity.
The answer is A.
Boxers wear gloves that are padded to lessen the force of a punch. Calculate the force exerted by a boxing glove on an opponent's face, if the glove and face compress 8.50 cm during a blow in which the 7.00-kg arm and glove are brought to rest from an initial speed of 10.0 m/s. Give your answer in Newtons, do not include the unit in your answer.
Answer:
F = 4117.64
Explanation:
First, we will calculate the acceleration of the hand, by using the third equation of motion:
[tex]2as = v_f^2 - v_i^2\\[/tex]
where,
a = acceleration = ?
s = distance covered = compression = 8.5 cm = 0.085 m
vf = final speed = 0 m/s
vi = iniial speed = 10 m/s
Therefore,
[tex]2a(0.085\ m) = (0\ m/s)^2-(10\ m/s)^2\\a = - 588.23\ m/s^2[/tex]
negative sign hows deceleration.
Now, we will calculate the force exerted by the hand:
[tex]F = ma = (7\ kg)(588.23\ m/s^2)\\[/tex]
F = 4117.64 N
A laser pulse of duration 25 ms has a total energy of 1.4 J. The wavelength of this radiation is
567 nm. How many photons are emitted in one pulse? Let 1 eV = 1.60 x 10-19 J, the mass of
an electron m=9.11 10-31
kg, the speed of light c= 3.00 x 108 m/s, and Planck's constant h
= 4.136 10-15 eV .s.
Answer:
n = 4 x 10¹⁸ photons
Explanation:
First, we will calculate the energy of one photon in the radiation:
[tex]E = \frac{hc}{\lambda}\\\\[/tex]
where,
E = Energy of one photon = ?
h = Plank's Constant = 6.625 x 10⁻³⁴ J.s
c = speed of light = 3 x 10⁸ m/s
λ = wavelength of radiation = 567 nm = 5.67 x 10⁻⁷ m
Therefore,
[tex]E = \frac{(6.625\ x\ 10^{-34}\ J.s)(3\ x\ 10^8\ m/s)}{5.67\ x\ 10^{-7}\ m}[/tex]
E = 3.505 x 10⁻¹⁹ J
Now, the number of photons to make up the total energy can be calculated as follows:
[tex]Total\ Energy = nE\\1.4\ J = n(3.505\ x\ 10^{-19}\ J)\\n = \frac{1.4\ J}{3.505\ x\ 10^{-19}\ J}\\[/tex]
n = 4 x 10¹⁸ photons
what is Laminar flow??
Answer:
Explanation:
Laminar Flow is a very important topic discussed in physics in the subject of fluid dynamics. Basically, it explains how fluid particles behave at lower velocities. In such cases and when the viscosity of the fluid is low, the fluid particles flow smoothly in perfectly perpendicular layers that do not collide or cross each other. Unlike turbulent flow, which is the opposite. An example of Laminar flow can be seen when you open up a water hose with little pressure, the water simply flows out of the hose and looks very clear and smooth.
In a car collision, is it better for the passenger if the change in momentum is over a short period of time or a long period of time?
Explanation:
The force on the passenger will be F = ma
Here, m does not change, but a is the variable.
If the cars slows down very fast, the acceleration will be higher, and thus the force will be higher.
If the acceleration is lower, the force will be lower as well, which would be the most desirable scenario for the passenger.
A spring gun with a spring constant of 250N/m is compressed 5.0cm. How fast will a 0.025kg dart move when it leaves the gun?
Answer:
1.5 m/s
Explanation:
The dart moves when it leaves the spring gun with a velocity of 22.4 m/s.
What is Potential energy?Potential energy is defined as the stored energy that depends on the relative position of different parts of a system such as springs have more potential energy when it will be compressed or stretched.
For velocity calculation of the dart when it leaves the spring gun, using the formula for potential energy stored in a spring:
[tex]PE = (1/2)kx^2[/tex]
where,
k is the spring constant
x is the compression of the spring.
Since the spring is compressed by 5 cm, the potential energy stored in it is:
[tex]PE = (1/2)(250 N/m)(0.05 m)^2[/tex]
PE = 6.25 J
The potential energy stored in the spring will be transferred to the dart when it is released which can be calculated from the velocity of the dart using the equation of conservation of energy:
[tex]PE = (1/2)mv^2[/tex]
where,
m is the mass of the dart
v is its velocity.
Solving for v:
v = sqrt(2PE/m)
=> sqrt(2(6.25 J)/(0.025 kg))
=> 22.4 m/s.
Thus, the dart moves when it leaves the spring gun with a velocity of 22.4 m/s.
Learn more about Velocity, here:
brainly.com/question/25287332
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A wheelbarrow can be used to help lift a load, such as a pile of dirt, and then push the load across a distance. A man pushes a wheelbarrow.
Answer:
B.) a wheel and axle and a lever
Explanation:
P.S - The exact question is -
Given - A wheelbarrow can be used to help lift a load, such as a pile of dirt, and then push the load across a distance. A man pushes a wheelbarrow.
To find - Which simple machines make up a wheelbarrow?
A.) a pulley and an inclined plane
B.) a wheel and axle and a lever
C.) a pulley and a wheel and axle
D.) a lever and a wedge
Proof -
The correct option is - B.) a wheel and axle and a lever
Wheelbarrows are used to carry more goods from place to place by using minimal force as compared when goods are carried by hand.
With this machine, During hauling people can save time.
Answer:
B.) a wheel and axle and a lever
Explanation:
to transmit heat sound or electricity through a medium
Answer:Electrical conduction is the transfer of electrically charged particles through a medium, such as electricity traveling through the power lines in your house. Sound conduction (or acoustic conduction) is the transfer of sound waves through a medium, such as vibrations from loud music passing through a wall.
Explanation: Trust
which statement identifies a reason to preserves wetlands
Answer:
They store floodwater
Explanation:
Consider these scenarios. A pink box with containing the words Scenario 2 You are about 7 meters away from a metal bar that is struck with a drumstick. The sounds travels through the air to your ear. In which of these scenarios would the sound of the drumstick hitting the metal bar get to you in the least amount of time? Explain your answer.
Answer:
Scenario 1 will cause the sound of the drumstick hitting the metal bar to reach your ears in the least amount of time.
Explanation:
The sound wave will travel faster in the metal bar than through the air because the speed of sound waves in solids is faster than it is in gases.
Answer:
Scenario 1 will cause the sound of the drumstick hitting the metal bar to reach your ears in the least amount of time.
Explanation:
ifunny is dankreloaded
Which wave must have a medium to travel?
A) light wave
B)compression wave
C) electromagnetic wave
D) ultraviolet wave
Explanation:
light waves because the categorised under mechanical waves
3.Three resistors of 25.0Ω, 30.0Ω, and 40.0Ω are in a series circuit with a 6.0-volt battery. What is the current in the circuit?
please answer by steps
Answer:
Current = 0.063 Amperes
Explanation:
Let the three resistors be R1, R2, and R3 respectively.
Given the following data;
R1 = 25.0Ω,
R2 = 30.0Ω
R3 = 40.0Ω
Voltage = 6 Volts
First of all, we would determine the equivalent or total resistance;
Total resistance (in series) = R1 + R2 + R3
Total resistance = 25.0Ω + 30.0Ω + 40.0Ω
Total resistance = 95 Ω
Next, we find the current flowing through the circuit;
Voltage = current * resistance
Substituting into the formula, we have;
6 = current * 95
Current = 6/95
Current = 0.063 Amperes
If someone replenishes the tree population in a forest ecosystem, how
might this affect the producers already living there?*
a: Increase in competitionfor biotic factors
b:decrease in competition for abiotic factors
c:increase in competition for abiotic factors
d: decrease in competition for biotic factors
Answer:
it would be c, an increase in competition for abiotic factors because if more trees are to be planted, less sunlight would seep through the leaves, leaving the producers to gain the abiotic factors to do with sunlight, temperature, and water
I hope this helps!!
have a wonderful day!
-millie :D
Green light (520 nm) enters glass with n = 1.52. What is the wavelength of light that enters the glass?
Answer:
answer=1.97×10^8
Explanation:
will u mark me brainliest?
Green light (520 nm) enters glass with n = 1.52, the wavelength of light that enters the glass is 520 nm.
To find the wavelength of light that enters the glass, we can use Snell's Law, which relates the angles and indices of refraction for light passing through a boundary between two mediums:
n₁ × sin(θ₁) = n₂ × sin(θ₂)
In this scenario, we can assume that the angle of incidence is zero degrees (the light is entering the glass perpendicular to the surface). Therefore, sin(θ₁) becomes sin(0) which is 0.
Using Snell's Law, we have:
n₁ × sin(θ₁) = n₂ × sin(θ₂)
1 × 0 = 1.52 × sin(θ₂)
The wavelength of light that enters the glass remains the same as the initial wavelength in air, which is 520 nm (nanometers).
Thus, the wavelength of light that enters the glass is 520 nm.
For more details regarding wavelength, visit:
https://brainly.com/question/31143857
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given a force of 100 N and a acceleration of 5 m/s, what is the mass
Answer:
[tex]force = mass \times acceleration \\ 100 = m \times 5 \\ m = \frac{100}{5} \\ m = 20 \: kg[/tex]
How does a mass drive work
Answer:
A mass driver or electro magnetic catapult is a proposed method of non-rocket space launch which would use a linear motor to accelerate and catapult payloads up to high speeds. All existing and contemplated mass drivers use coils of wire energized by electricity to make electromagnets.
Explanation:
may i be marked brainliest?
particles q1, q2, and q3 are in a straight line. particles q1 = -5.00 x 10^-6 C, q2 = -5.00 x 10^-6 C. .5 between each what is the net force on q3
Answer:
1.12
Explanation:
Acellus
Answer: +1.12
Explanation:
This answer works for Acellus! :)
How can you make two objects with different masses move the same distance
Answer:
apply more energy to the object with more mass
Explanation:
in the experiment it is important to make measurements that are both precise and accurate
which of these measurements of time is the most precise
5.1 second s
5.14 second s
5 second s.
If a cart at the top of a hill has 50 newtons of pot. energy what will it have when it comes down?
Answer:
50 newtons of kenetic energy?? im guessing ngl
Explanation:
How would the motion of the book change if there was MORE friction as it moved across the table?
Answer:
The force of friction opposes the motion of an object, causing moving objects to lose energy and slow down.
Explanation:
An object is in motion if ___
Answer:
An object is in notion if its position change with time.
Qs 5 pleaseeee help!!!
Answer:
Ok, first is important that you understand how the heat radiation works.
All the objects that have some heat energy in them, radiate some of that energy in the form of electromagnetic waves.
Particularly, the Sun radiates a lot of energy (at the point that if you step under the sunlight, you can feel on your skin the heat that comes from the sun, this is due to radiation).
Now, suppose that you have a thin coat of water over you, then the material that gets impacted by that radiation will be the water and not you, and then the energy is dissipated (some of the energy goes to your body and some go to the air)
This is one way in which spraying water over themselves helps the elephants to keep them cool.
Another way in which heat can be transferred is by conduction.
When you have a hot object and a cool object, and you put them together (so the objects touch each other), the heat will flow from the hotter object to the cooler object until both objects have the same temperature.
Then if the elephant body temperature is larger than the temperature of the water that the elephant sprays over his body, when the water touches the body some of the heat in the elephant body will be transferred to the coat of water, and in this way, the temperature of the elephant's body decreases.
These are the two ways we wanted to find.
When an electron is removed from a neutral atom, it becomes....
A) A positive ion
B) a negative ion
C) heavier
D) a bipolar atom
Answer:
A
Explanation:
Which of the following statements is true for a ball thrown vertically upward