Answer:
Use of lubricants: In machines, friction can be reduced by applying lubricants between the contact surfaces to fill the fine pores or depressions in the surfaces and make them smooth thereby reducing friction. Polishing : unevenness of the surfaces can be reduced by polishing, thereby reducing the friction.
Explanation:
The purpose of a cell phone cover is to protect your phone from impact forces. How does a cell phone case do this?
Answer:
it covers your phone so when you drop it it reduces the chance and breaking
I WILL GIVE BRAINLIEST....
Determine the value of F...
At least ____________________ inches of free conductor, measured from the point in the box where it emerges from its raceway or cable sheath, must be left at each outlet, junction, or switch point for the connection of luminaires or devices.
Answer:
150mm
Explanation:
The correct answer to the given question is 150mm or 6 inch.
Atleast 150mm or 6 inches of a free conductor, measured from the point in box where it emerges from its cable sheath or raceway, must be left at each outlet, switch or junction point to lumination or connection of devices.
150mm of free conductor is required for the devices to be connected, this needs to be placed in the junctions
What is a pure spectrum?
Answer:
a spectrum in which the dispersion is highly discriminative so that at each point the light is practically monochromatic.
A 2.0 kg block is pulled across a horizontal surface by a 15 N force at a constant velocity. What is the force of friction acting on the block?
Answer:
The force of friction acting on the block has a magnitude of 15 N and acts opposite to the applied force.
Explanation:
Net Force
The Second Newton's law states that an object acquires acceleration when an unbalanced net force is applied to it.
The acceleration is proportional to the net force and inversely proportional to the mass of the object.
If the object has zero net force, it won't get accelerated and its velocity will remain constant.
The m=2 kg block is being pulled across a horizontal surface by a force of F=15 N and we are told the block moves at a constant velocity. This means the acceleration is zero and therefore the net force is also zero.
Since there is an external force applied to the box, it must have been balanced by the force of friction, thus the force of friction has the same magnitude acting opposite to the applied force.
The force of friction acting on the block has a magnitude of 15 N opposite to the applied force.
How much would a 25 kg suitcase weigh on the surface of…?
a. Mercury
b. Mars
c. Saturn
d. Pluto
Answer:
a) [tex]W_{Mercury}=92.5 N[/tex]
b) [tex]W_{Mars}=92.8 N[/tex]
c) [tex]W_{Saturn}=261.0 N[/tex]
d) [tex]W_{Pluto}=15.5 N[/tex]
Explanation:
First of all, we need to remember the value of gravity acceleration on each planet.
[tex]g_{Mer}=3.70 m/s^{2}[/tex]
[tex]g_{Mar}=3.71 m/s^{2}[/tex]
[tex]g_{Sat}=10.44 m/s^{2}[/tex]
[tex]g_{Plt}=0.62 m/s^{2}[/tex]
The definition of weigh is the product between the mass and the gravity acceleration, therefore we will have:
a) [tex]W_{Mercury}=25*3.70=92.5 N[/tex]
b) [tex]W_{Mars}=25*3.71=92.8 N[/tex]
c) [tex]W_{Saturn}=25*10.44=261.0 N[/tex]
d) [tex]W_{Pluto}=25*0.62=15.5 N[/tex]
I hope it helps you!
Why can you see an apple as green and not red?
Answer:
A lot of Dietary Fiber.
Explanation:
Answer:
Red apples get their color from anthocyanins. These are pigments, or natural colorings, that develop as the apple grows. ... It absorbs all the colors of the rainbow—except for red. The red light reflects off the apple and our brain and eyes work together to let us know what color we are seeing.
1. Which of the following best describes a neutral solid object that is charged by conduction?
The electrons in the neutral solid object relocate when a charged object is brought near.
The protons in the neutral solid object relocate when a charge object is brought near.
The electrons in the neutral object transfer onto a positively charged object.
The protons in the neutral object transfer onto a negatively charged object.
Answer:
C: The electrons in the neutral object transfer onto a positively charged object.
Explanation:
In conduction, when we charge one object with another, both of them will now have the same type of charge. Thus, in conduction, a positive object is used to charge a neutral object, then it means that both objects become charged positively charged. Electrons are positive charges.
Thus electrons in the neutral object are transferred onto a positively charged object and so option C is right.
3. If there is an atomic mass of 47
and the atomic number is 20,
how
many protons and neutrons
are there?
Answer:
20
27
Explanation:
Given parameters:
Atomic mass = 47
Atomic number = 20
Unknown:
Number of protons = ?
Number of neutrons = ?
Solution:
To solve this problem,
Atomic mass = number of protons + number of neutrons
Atomic number = number of protons
So;
Number of protons = 20
Now;
Number of neutrons = Atomic mass - number of protons
Number of neutrons = 47 - 20 = 27
a brown bear runs at the speed of 9.0m/s with 23,000 j of kinetic energy
Is a car full of gas a closed system?
Answer:
Its An Open System
Explanation:
Answer: Open System
Explanation:
can i have brainly
A horse gallops a distance of 60 m and 15 seconds. Then, he stops to eat some grass for 20 seconds. Next, he trots for 25 seconds over 60 m. The horse trots in the same direction he galloped. Finally the horse races back home (back to it starting position) traveling 120 m in 20 seconds.
Calculate the horses average speed for the entire journey.
Please do a Step By Step!
Explanation:
120+ 120 = 240 miles divided 1 hours 20 seconds
A wave has frequency of 5 Hz and a speed of 25 m/s. What is the wavelength of the wave?
Answer:
A wave has a wavelength of 5 meters and a frequency of 3 hertz.
Explanation:
By what process do electromagnetic waves release electrons from the
materials they contact?
O A. The photoelectric effect
O B. Absorption of electromagnetic waves
O C. Flow of electrons from negative to positive poles
O D. Reflection of electromagnetic waves
Answer:
A.) the photoelectric effect
Explanation:
A hydrogen atom is isolated in a vacuum chamber, the electron is now separated from the proton and moved to a distance 1 cm away. Let Fg be the magnitude of the gravitational force between the proton and electron, and let Fe be the magnitude of the electric force between the proton and electron. How does the ratio Fg/Fe change as the particles are separated
Answer:
hello your question is incomplete attached below is the complete question
answer: Fg / Fe does not change ; it is the same nonzero value for all separations ( A )
Explanation:
Given that distance between proton and electron is 1 cm
Fg = Gm1m2 / r^2
where :
G ( gravitational constant )= 6.67 * 10^-11 Nm^2 / kg^2
m1 ( mass of proton ) = 1.67 * 10^-27 kg
m2 ( mass of electron ) = 9.11 * 10^-31 kg
Electrical force
Fe = kq1q2 / r^2
k = 9*10^9
hence ;
Fg / Fe = (Gm1m2 / r^2) / (kq1q2 / r^2 )
= Gm1m2 / kq1q2
HURRY! I HAVE 5 MIN LEFT!!!Robert picks up a metal pan lid that was covering a pot of boiling water, and he drops it immediately. Cells in his fingers sent the message that his finger had touched heat.
The message carried is the nerve impulse, which is transmitted to nearby cells. What is the space where one neuron can transmit the impulse to another neuron called?
Answer:
synapse
Explanation:
The message carried is the nerve impulse, which is transmitted to nearby cells. The space where one neuron can transmit the impulse to another neuron is known as a Synapse.
What is Neuron?
Neurons, also known as neurons or nerve cells, are the basic building blocks of the nervous system and brain. They are the cells in charge of receiving sensory information from the outside world, trying to send motor commands to with us muscles, and converting and relaying electrical signals at each stage along the way.
However, their interactions also shape what we are as people. However, our about 3 trillion neurons do connect with some other cell types that are generally referred to as glia in a close manner.
Visualizing a cell as a tree is a helpful analogy. Three essential components of a neuron are dendrites, an axon, and a cell body, or soma, that can be compared to the branches, foundations, and core of a tree, correspondingly.
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A child and sled with a combined mass of 26.3 kg slide down a frictionless hill. The sled starts from rest and acquires a speed of 5.34 m/s by the time it reaches the bottom of the hill. What is the height (in m) of the hill?
Answer:
12 m/s
Explanation:
A cube has sides of length 10 cm and weighs 10 N.
Calculate the pressure when it rests on one side ....N/cm2
Answer:
P = r g h where r here is the density m / V and then P is the pressre.
W (weight) = m g
m = 10 N / 9.8 m / s^2 = 1.02 kg
r (density) = m / V = 1.02 kg / 1000 cm^3 = .00102 kg/cm^3
P = .00102 kg / cm3 * 9.8 m/s^2 * 10 cm
P = .1 kg m / (s^2 cm^2)
Since 1 N = kg m / s^2 then P = .1 N / cm^2
More simply P = F / A = 10 N / 100 cm^2 = .1 N / cm^2
which rock is most likely phyllite
Answer/Explanation:
Phyllite is a very common metamorphic rock, found in many parts of the world. It forms when sedimentary rocks are buried and mildly altered by the heat and directed pressure of regional metamorphism.
Answer:
metamorphic rock
Explanation:
Phyllite is a very common metamorphic rock, found in many parts of the world. It forms when sedimentary rocks are buried and mildly altered by the heat and directed pressure of regional metamorphism.
how temperature, surface tension and the diameter of the tube affect capillary action.
The surface tension acts to hold the surface intact. Capillary action occurs when the adhesion to the surface material is stronger than the cohesive forces between the water molecules. ... Water wants to stick to the glass and surface tension will push the water up, until the force of gravity prevents further rise.
Narrower tube openings allow capillary action to pull water higher
Which of the following is not a step toward planning your goal? A. Set a target date. B. Disregard o goal if you don’t achieve it. C. Set both short- and long-term goals. D. Reward yourself for a small accomplishment.
Answer:
B
Explanation:
Disregard a goal if you don't achieve it
2.Find the magnitude and direction of the resultant velocity vector for the following perpendicular velocities: a. a fish swimming at 3.0 m/s relative to the water across a river that moves at 5.0 m/s b. a surfer traveling at 1.0 m/s relative to the water across a wave that is traveling at 6.0 m/s
Answer:
a. The magnitude of the resultant velocity vector of the fish is approximately 5.83 m/s
The direction of the resultant velocity vector of the fish is approximately 30.93° relative to the direction of the river
b. The magnitude of the resultant velocity vector of the surfer is approximately 6.083 m/s
The direction of the resultant velocity vector of the surfer is approximately 9.46° relative to the direction of the wave
Explanation:
a. The given parameters of the fish and the river are;
The speed with which the fish is swimming across the river, v₁ = 3.0 m/s
The velocity with which the river is flowing, v₂ = 5.0 m/s
Therefore, in vector form, we have;
v₁ = 3.0·j
v₂ = 5.0·i
The resultant velocity, R = v₁ + v₂ = 5.0·i + 3.0·j
∴ R = 5.0·i + 3.0·j
The magnitude of the resultant velocity vector, [tex]\left | R \right |[/tex] = √(5.0² + 3.0²) =√34 ≈ 5.83
The magnitude of the resultant velocity vector, of the fish, [tex]\left | R \right |[/tex] ≈ 5.83 m/s
The direction of the resultant velocity of the fish, θ = arctan(3.0/5.0) ≈ 30.93°
Therefore, The direction of the resultant velocity vector of the fish, θ ≈ 30.93° relative to the direction of the river
b. The given parameters of the surfer and the wave are;
The speed with which the surfer is travelling, v₁ = 1.0 m/s
The speed of the wave travelling across, v₂ = 6.0 m/s
Therefore, in vector form, we have;
v₁ = 1.0·j
v₂ = 6.0·i
The resultant velocity, R = v₁ + v₂ = 1.0·i + 6.0·j
∴ R = 1.0·i + 6.0·j
The magnitude of the resultant velocity of the surfer, [tex]\left | R \right |[/tex] = √(1.0² + 6.0²) =√37 ≈ 6.083
The magnitude of the resultant velocity vector of the surfer, [tex]\left | R \right |[/tex] ≈ 6.083 m/s
The direction of the resultant velocity of the surfer, θ = arctan(1.0/6.0) ≈ 9.46°
Therefore, The direction of the resultant velocity vector of the surfer, θ ≈ 9.46° relative to the direction of the wave
Are the divisions of the electromagnetic spectrum distinct? Explain your answer
Answer:
No
Explanation:
Are the divisions of the electromagnetic spectrum distinct?
The answer is NO.
To explain my answer, there are some points to be noted
1.) There are no clear divisions between the different ranges or bands in the electromagnetic spectrum. The divisions are somewhat arbitrary
2.) The naming of subdivisions is also arbitrary. For instance, microwaves are sometimes regarded as a subdivision of radio waves
3.) The ranges of x-ray and gamma ray overlaps
a 2.00kg cart travelling north at 4.00m/s collides head on with a 1.00kg cart travelling south at 8.00m/s. what is the magnitude of the total momentum of the two carts after the collision
Answer:
16 kgm/s
Explanation:
Step one:
given data
m1= 2kg
v1= 4 m/s
m2= 1kg
v2= 8m/s
Required
The magnitude of momentum after impact pafter
Momentum is the product of a moving object's mass and velocity
Step two:
Pa= m1v1+m2v2
Pa=2*4+1*8
Pa=8+8
Pa=16 kgm/s
What are two reasons that digital storage of data is so reliable?
O A. Digital data are easy to change.
B. Digital data can usually be recovered even if the storage device
stops working.
C. Copied data decrease in quality each time a copy is made.
D. Memory chips do not break easily.
Answer:
it will option C this is the correct answer of this question
Digital data can usually be recovered even if the storage device if it stops working and memory chips don't break easily. So, the correct options are B and D.
What is Digital storage?Digital storage of data is defined as the process that usually involves saving computer files or documents on magnetic storage devices, usually flash memory which may include hard drives, memory sticks or cards, optical discs , cloud storage, etc. are included.
Reliable storage ensures that which computer files or documents are easily accessible and can be recovered in the event of loss. Digital data can usually be recovered even if the storage device fails, as long as the memory chips are not easily breakable.
So, the correct options are B and D.
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A spring with a spring constant of 500 N/m is stretched 1 meter in length. How much elastic potential energy does the spring have stored in it?
Answer:
E =250 J
Explanation:
Given that,
The spring constant of the spring, k = 500 N/
It is stretched to a distance of 1 m
We need to find how much elastic potential energy does the spring have stored in it.
The energy stored in the spring is called elastic potential energy. It is given by the formula as follows :
[tex]E=\dfrac{1}{2}kx^2\\\\E=\dfrac{1}{2}\times 500\times 1^2\\\\E=250\ J[/tex]
So, 250 J of energy is stored in the spring.
calculate the net force and the acceleration the block
Answer:
The net force is 20 N and the acceleration of the block is [tex]5\ m/s^2[/tex]
Explanation:
Given that,
Mass of the block, m = 4 kg
Force in right side = 30 N
Force in left side = 10 N
We need to find the net force and the acceleration of the block.
Net force = Right force - left force (as both are opposite to each other)
= 30 N - 10 N
= 20 N
Formula for net force,
F = ma
a is acceleration
[tex]a=\dfrac{F}{m}\\\\a=\dfrac{20\ N}{4\ kg}\\\\a=5\ m/s^2[/tex]
Hence, the net force is 20 N and acceleration of the block is [tex]5\ m/s^2[/tex].
The purpose of a cell phone cover is to protect your phone from impact forces. How does a cell phone case do this?
Answer:
the material of the phone case
The purpose of a cell phone cover is to protect your phone from impact forces. It is done by absorbing the impact of force by back cover.
What is Force ?
Force is responsible for the motion of an object. it produces acceleration in the body. According to newton's second law force is mass times acceleration i.e. F =ma. Its SI unit is N which is equivalent to kg.m/s².
The case is made in such a way that, if the cell phone is dropped, the cover will absorb the kinetic energy of the falling phone by the means of deforming without transferring the impact onto the phone.
Cell phone cover is made up of rubber which can restore the forces like a spring. when u apply force to the rubber it get displaced and applied force is stored in the rubber. when cell phone drops, rubber of the cover absorbs the energy of impact. it also provides shied protection to the phone.
Hence this is how cell phone case do this.
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Earth travels fastest in January and slowest in July. What is the most likely explanation for this?
A. Earth is nearest the Sun in July and farthest away in January.
B. Earth is nearest the Sun in January and farthest away in July.
C. Earth is nearest the Sun in April and farthest away in October.
D. Earth is nearest the Sun in October and farthest away in April.
Answer:
Earth is nearest the Sun in July and farthest away in July.
Explanation:
Answer:
Correct Answer: B.
Explanation:
Earth is nearest the Sun in January and farthest away in July. Explanation: According to Kepler's Second Law, a planet travels fastest when it is nearest its sun. This means that Earth is actually closest to the Sun in January, when it is winter in the northern hemisphere!
Why would it be incorrect to say that the bulb supplies 60 J of light energy energy each second
Answer:
Explanation:
A 60W bulb , consumes electrical energy of 60 J per second but it does not give out all the energy in the form of light . Most of the energy consumed by it is wasted in the form of heat . Only a fraction of energy is converted into light energy .
Hence, it is wrong to say that bulb supplies 60 J of light energy each second .