Answers
If the box is moving at constant velocity, net force must be zero, so:
F + fr = 0
fr = -F
fr = -40 N
Related Questions
What is meant by child rights?
Answers
Any violation of these rights could lead to the child being put into CPS or the violator being sent to jail.
Hope this helps you
What is the slope of the line that passes through the points (-8, -3)(−8,−3) and (-12, -3) ?(−12,−3)? Write your answer in the simplest form.
single black dude
Answers
Notice that both of those points are 3 units below the x-axis. So the line is horizontal ... its slope is zero.
A satellite orbits the Earth (mass = 5.98 x 1024 kg) once every = 43200 s. At what radius does the satellite orbit?
Answers
Answer:
26621 km
Explanation:
We are given;
Mass: m = 5.98 x 10^(24) kg
Period; T = 43200 s
Formula for The velocity(v) of the satellite is:
v = 2πR/T
Where R is the radius
Formula for centripetal acceleration is;
a_c = v²/R
Thus; a_c = (2πR/T)²/R = 4π²R/T²
Formula for gravitational acceleration is:
a_g = Gm/R²
Where G is gravitational constant = 6.674 × 10^(-11) m³/kg.s²
Now the centripetal acceleration of the satellite is caused by its gravitational acceleration. Thus;
Centripetal acceleration = gravitational acceleration.
Thus;
4π²R/T² = Gm/R²
Making R the subject gives;
R = ∛(GmT²/4π²)
Plugging in the relevant values;
R = ∛((6.674 × 10^(-11) × 5.98 x 10^(24) × 43200²)/(4 × π²))
R = 26.621 × 10^(6) m
Converting to km, we have;
R = 26621 km
Answer:
2.66 *10^7
Explanation:
Sorry I don't know the process if you were interested in that :/
A missle is flying at a speed 125 m/s. if the missle has a mass of 125 kg. What’s it’s kinetic energy
Answers
Answer:
[tex]976562.5\ Joules[/tex]
Explanation:
[tex]We\ are\ given:\\The\ mass\ of\ the\ missile=125\ kg\\The\ velocity\ of\ the\ missile=125\ m/s\\Hence,\\As\ we\ know\ that,\\Kinetic\ energy\ possessed\ by\ an\ object\ with\ mass\ m\ moving\\ with\ a\ velocity\ v:\\E_k=\frac{1}{2}mv^2\\Here,\\The\ Kinetic\ Energy\ possessed\ by\ the\ missile=\frac{1}{2}*125*(125)^2=976562.5\ Joules[/tex]
A block with a mass of 0.30 kg is attached to a horizontal spring. The block is pulled back from its equilibrium position until the spring exerts a force of 1.2 N on the block. When the block is released, it oscillates with a frequency of 1.1 Hz.
How far was the block pulled back before being released?
Answers
Answer:
The value is [tex]x = 0.084 \ m[/tex]
Explanation:
From the question we are told that
The mass of the block is [tex]m = 0.30 \ kg[/tex]
The force exerted is [tex]F = 1.2 \ N[/tex]
The frequency is [tex]f = 1.1 \ Hz[/tex]
Generally the spring constant of the spring is mathematically represented as
[tex]k = (2 \pi f)^2 * m[/tex]
=> [tex]k = (2 * 3.142 * 1.1 )^2 * 0.30[/tex]
=> [tex]k = 14.33 \ N/m[/tex]
Generally the spring constant is also mathematically represented as
[tex]k = \frac{ F }{x }[/tex]
=> [tex]14.33 = \frac{ 1.2 }{x }[/tex]
=> [tex]x = 0.084 \ m[/tex]
The diagram shows an electromagnet made with copper wire, a steel nail,
and a 1.5 V battery. Which change would make this electromagnet weaker?
A. Reverse the direction of the battery
B. Rap more coils around the nail
C. Replace the steel nail with a wooden stick
D. Replace the battery with a 3V battery
Correct answer is C
Answers
If an electromagnet is made with copper wire, a steel nail, and a 1.5 V battery then replacing the steel nail with a wooden stick would make this electromagnet weaker, therefore the correct answer is option C.
What is electromagnetic force?It is a type of force that occur between electrically charged particles. The electromagnetic force is the combination of all the electrical and magnetic forces generated by any charged particle.
As given in the problem statement diagram shows an electromagnet made with copper wire, a steel nail, and a 1.5 V battery, then we have to find out which change would make this electromagnet weaker,
Hence, By replacing the steel nail with a wooden stick would make this electromagnet weaker, therefore the correct answer is option C.
To learn more about electromagnetic forces, refer to the link;
brainly.com/question/13191643
#SPJ5
HELP ASAP!! i’ll mark you the brainliest!!
Answers
Answer:
yes
Explanation:
1. Derive the equation of the trajectory of a projectile.
(3mks)
2. A ball is thrown with an initial speed uof 30 m/s at an angle & above thehorizontal, where
sin 0 = 4/5 and cos 0 = 3/5.
(5mks)
(a) decompose the vector u into itsx and y components.
(b) When t= 2 s, find the position of the ball andthe magnitude and direction of its
velocityu.
(c) Determine
the value
of the highest point of the ball's trajectory.
(d) calculate how much time has elapsed forthe ball to reach the highest point.
(e) Calculate the values of the total time of theball's flight T and the horizontal range R.
ASAN
3. In the model of the hydrogen atom proposed by Niels Bohr an electron circulatesa
stationary proton in a circle of radius 7' = 5.28 x 10-11 m with a speedı= 2.18 x 106m's
(a) Find the magnitude of the electron sradial acceleration in this model.
(1mk)
(b) Determine the period of the motion,
(Imk)
Answers
Based on the law of conservation of energy, which statement is correct?
A.
Energy is always being added to all parts of the Universe.
B.
Energy is often destroyed in some parts of the Universe.
C.
Energy in a closed system cannot change forms.
D.
Energy in an isolated system remains constan
Answers
Answer:
D
Explanation:
Nothing can enter or leave so it remains constant
A car moving initially at 20 m/s accelerates up to 60 m/s during the
course of 5 seconds. The average acceleration of the car is m/s2
Answers
Time taken for this gain = 5 seconds
Average acceleration = 30 / 5 = 6 m/s/s.
So, 6 metres per second squared.
472 viewsView 2 Upvoters
Related Questions (More Answers Below)
In specific heat capacity experiment, the ammeter in circuit is connected in
Answers
Answer:
In series
Explanation:
In such experiment, the ammeter is connected in series with the heater, in order to measure the circulating current.
By the way, ammeters are always connected in series in circuits to measure the running current in it.
a 2kg block is attached to a horizontal ideal spring with a spring constant of 200 Newton per minute. when the spring has its equillibrium length of block is given a speed of 5mps. what is the maximum elongation of the spring
Answers
Answer:
The maximum elongation of the spring is 0.5 meters.
Explanation:
The statement is incorrect. The correct form is:
A 2-kg block is attached to a horizontal ideal spring with a spring constant of 200 newton per meter. When the spring has its equillibrium length, the block has a speed of 5 meters per second. What is the maximum elongation of the spring?
The block experiments a simple harmonic motion, where there are no non-conservative forces and the total energy is the sum of translational kinetic energy of the mass and the elastic potential energy of the spring. The maximum elongation of the spring is done when elastic potential energy reach its maximum. By the Principle of Energy Conservation, the maximum elastic potential energy is equal to the maximum translational kinetic energy, which corresponds to the instant when the mass reaches the equilibrium position. Then, the equation modelling the system is:
[tex]U_{max} = K_{max}[/tex] (1)
Where:
[tex]U_{max}[/tex] - Maximum elastic potential energy of the spring, measured in joules.
[tex]K_{max}[/tex] - Maximum translational kinetic energy of the mass, measured in joules.
By definitions of the maximum elastic potential energy of the spring and the maximum translational kinetic energy of the mass, the expression above is expanded and simplified:
[tex]\frac{1}{2}\cdot k\cdot x_{max}^{2} = \frac{1}{2}\cdot m \cdot v_{max}^{2}[/tex]
[tex]x_{max} = \sqrt{\frac{m}{k} }\cdot v_{max}[/tex] (2)
Where:
[tex]x_{max}[/tex] - Maximum elongation of the spring, measured in meters.
[tex]m[/tex] - Mass, measured in kilograms.
[tex]k[/tex] - Spring constant, measured in newtons per meter.
[tex]v_{max}[/tex] - Maximum speed of the mass, measured in meters per second.
If we know that [tex]m = 2\,kg[/tex], [tex]k = 200\,\frac{N}{m}[/tex] and [tex]v_{max} = 5\,\frac{m}{s}[/tex], then the maximum elongation of the spring is:
[tex]x_{max} = \sqrt{\frac{2\,kg}{200\,\frac{N}{m} } }\cdot \left(5\,\frac{m}{s} \right)[/tex]
[tex]x_{max} = 0.5\,m[/tex]
The maximum elongation of the spring is 0.5 meters.
100 points!! word bank!
⬇️Article⬇️
Have you ever cut an apple in half and looked at the layers inside? When you cut something in half, the resulting view is called a cross section. When you look at the cross section of an apple, you see several layers: the skin, the pulp, the core, and the seeds. Much like the apple, Earth is made up of layers, too. If you could look at a cross section of our planet, you would see the crust. the mantle, the outer core, and the inner core. If Earth were an apple, the crust would be the apple’s skin. The mantle would be the apple’s pulp, making up most of the inside. Earth also has a central core, similar to an apple’s core, though Earth’s core does not contain any seeds! Of course, scientists cannot cut the whole planet in half to see a cross section the way you can with an apple. How do you think scientists know about Earth’s internal layers?
Scientists divide Earth’s interior into distinct layers.
Scientists can distinguish different layers in Earth depending on the properties used to identify each layer. For example, scientists identify the crust, mantle, and core based on each layer’s basic chemical composition. In other words, the crust, mantle, and core are each made up of different chemical elements. The crust and mantle are composed primarily of the elements oxygen and silicon. These are known as silicates. Silicates of the mantle contain heavier elements. This makes them denser than those found in the crust. The core is composed of the densest materials, primarily iron and nickel. Earth’s layers can also be identified by using each layer’s physical state of matter. The crust and the uppermost part of the mantle, together, make up a layer called the lithosphere. The lithosphere is the cool, rigid, outermost layer of Earth. The lithosphere is in the solid
In a typical silicate molecule, a silicon atom is bonded to four oxygen atoms. The atoms form a crystal structure.
Scientists use models to represent the different layers of Earth’s interior.
When constructing a model of the layers of Earth, scientists need to consider the chemical composition, state of matter, and thickness of each layer. Just like the skin of an apple, Earth’s crust is very thin compared to the other layers. It is about 25–70 km thick beneath the continents. Under the oceans, the crust is only about 5–7 km thick; however, it is much denser. The mantle is much thicker than the crust is, taking up most of Earth’s volume. The mantle begins directly beneath Earth’s crust. It reaches all the way to the outer core, about 2,900 km below the planet’s surface. In other words, Earth is about 1% crust, 83% mantle, and 16% core.
The crust and uppermost mantle are solid. The rest of the mantle is solid with plasticity. The core is made of very dense iron and nickel. The outer core is liquid, because it is hot enough to melt the iron and nickel. The inner core is solid. Even though it is as hot as the outer core, there is so much pressure at the very center of Earth that the iron and nickel stay in a solid state.
Looking to the Future: Exploring Earth’s Interior
Despite what you may have read in stories or seen in movies, scientists have never journeyed to the center of Earth. In fact, scientists have never made it through Earth’s crust! However, this has not stopped them from trying. The crust at the bottom of the oceans is much thinner than the crust of the continents. Therefore, drilling through the oceanic crust is the best chance that scientists have to make it to the mantle.
Answers
Answer:
Except in the crust, the interior of the Earth cannot be studied by drilling holes to take samples. Instead, scientists map the interior by watching how seismic waves from earthquakes are bent, reflected, sped up, or delayed by the various layers.
Explanation:
One of the two rectangular components of a force is 20N and it makes an angle of 30
with the force. Find the magnitude of the other components.
Answers
Answer:
11.545NExplanation:
The the horizontal and vertical component be expressed as;
Fx = Fxos theta (horizontal compt)
Given Fx = 20N
theta = 30°
Get F:
20 = Fcos30
20 = 0.8660F
F = 20/0.8660
F = 23.09N
Get the magnitude of the other components. (vertical compt)
Fy = Fsin theta
Fy = 23.09sin30
Fy = 23.09(0.5)
Fy = 11.545N
Hence the magnitude of the other component is 11.545N
Which of the following cars have the most kinetic energy
Answers
[tex]\huge\boxed{OptionA}[/tex]
_____________________________________DATA:Blue Car:mass = 4 kg
velocity = 5 m/s^2
Orange truck:Mass= 2kg
Velocity = 7m/s^2
Grey Car:mass = 6 kg
velocity = 4m/s^2
Green Car:Mass = 8 kg
Velocity = 3 m/s^2
_____________________________________SOLUTION:By the equation of kinetic energy,
K.E = [tex]\frac{1}{2} mv^2[/tex]
Where,
K.E is kinetic energy
m is mass
v is velocity
_____________________________________Kinetic energy of Blue car:
Directly substitute the variables in the equation,
K.E = [tex]\frac{1}{2}x4x5^2[/tex]
Simplify the equation,
K.E = 50 J
_____________________________________Kinetic Energy of Silver Car:
Directly substitude the variable in the equation,
K.E = [tex]\frac{1}{2}x6x4^2[/tex]
Simplify the equation,
K.E = 48J
_____________________________________Kinetic Energy of Green Car:Substitute the variables in the equation,
K.E = [tex]\frac{1}{2}x8x3^2[/tex]
Simplify the Equation,
K.E = 36J
_____________________________________Kinetic Energy of Orange Truck:Substitute the variable,
K.E = [tex]\frac{1}{2}x 2x7^2[/tex]
Simplify the equation,
K.E = 49J
_____________________________________As you can see that the highest value of kinetic energy is of Blue SUV thus it will be out answer.
_____________________________________Best Regards,'Borz' How fast should a rocket ship move for its mass to be dilated to 167% of its rest
mass?
Answers
Answer:
The two forces acting on rockets at the moment of launch are the thrust upwards and the weight downwards. Weight is the force due to gravity and is calculated (at the Earth’s surface) by multiplying the mass (kilograms) by 9.8.The resultant force on each rocket is calculated using the equation resultant force = thrust – weight.
Hopefully, this answer helps you! :)
A 60-W light bulb radiates electromagnetic waves uniformly in all directions. At a distance of 1.0 mfrom the bulb, the light intensity is I0, the average energy density of the waves is u0, and the rms electric and magnetic field values are E0 and B0, respectively.
At 2.0 m from the bulb, what is the light intensity?
Answers
Answer:
I0/4
Explanation:
If the difference is increasedby a factor of two(i.e twice it's original value), then the light intensity happens to get reduced by one-fourth. This means that the light intensity would be:
I0/4
A quantity of hot water at 91°C and another cold one at 12°C.
How much kilogram of each one is needed to make an 800 liter of water bath
at temperature of 35°C.
Answers
Answer:
[tex]m_{cold}=567kg\\\\m_{hot}=233kg[/tex]
Explanation:
Hello!
In this case, since equilibrium temperature problems involve the mass, specific heat and temperature change for the substances at different temperatures, we can write:
[tex]m_{cold}C_{cold}(T_{eq}-T_{cold})=-m_{hot}C_{hot}(T_{eq}-T_{hot})[/tex]
Thus, since we are talking about water and they both have the same specific heat, we can write:
[tex]m_{cold}(T_{eq}-T_{cold})=-m_{hot}(T_{eq}-T_{hot})[/tex]
Now, we plug in the temperatures to obtain:
[tex]m_{cold}(35-12)+m_{hot}(35-91)=0\\\\23m_{cold}-56m_{hot}=0[/tex]
Next, since the total volume of water is 800 L, since it has a density of 1kg/L, we infer the total mass is 800 kg; that is why we can write a 2x2 system of simultaneous equations:
[tex]\left \{ {{23m_{cold}-56m_{hot}=0} \atop {m_{cold}+m_{hot}=800}} \right.[/tex]
Thus, the masses of both cold and hot water turn out:
[tex]m_{cold}=567kg\\\\m_{hot}=233kg[/tex]
Best regards!
a steel girder weighting 700 lb is hoisted from gund level to the roof of a 70-ft building using a chain that weighs 4lb/running foot. Find the work done
Answers
Answer:
66.475kJ
Explanation:
Work done is the product of the force and perpendicular distance in direction of the force.
Work done = Force × distance
Given
Weight = 700lb
Distance = 70ft
1lb force = 4.448N
700lb force = 700(4.448) = 3113.6N
Distance = 70(0.305) = 21.35m
Work done = 3113.6×21.35
Work done ≈ 66,475Joules
Work done = 66.475kJ
You have to move your 100 N couch before a delivery company drops off your new one. Unfortunately your roommate is passed out on it. The coefficient of friction between the couch and floor is .43. It takes 250 N of force to get the couch moving. a) How much does your roommate weigh in Newton’s? b) After you get the couch moving it only takes 200 N to keep it moving at a constant speed, what is the coefficient of kinetic friction?
Answers
Answer:
a) Weight of Roommate = 481.4 N
b) μk = 0.34
Explanation:
a)
The force required to move the couch must be equal to the force of friction:
F = frictional force
F = μW
W = F/μ
where,
W = Total Weight of Couch and Roommate
F = Force Required start to move couch = 250 N
μ = coefficient of static friction between couch and floor = 0.43
Therefore,
[tex]W = \frac{250 N}{0.43}\\\\W = 581.4 N[/tex]
So, the total weight is given as:
W = Weight of Couch + Weight of Roommate
Weight of Roommate = W - Weight of Couch
Weight of Roommate = 581.4 N - 100 N
Weight of Roommate = 481.4 N
b)
Now, the force required to keep the couch moving can be given as equal to the kinetic friction force:
F = kinetic friction
F = μk*W
μk = F/W
where,
μk = coefficient of kinetic friction = ?
F = Force required to keep the couch moving = 200 N
Therefore,
μk = 200 N/581.4 N
μk = 0.34
.
Calculate the potential energy of a 6 kg bowling ball suspended 3 m above the surface of the Earth.
Answers
Answer: 176.4 J
Explanation:
6. Which statement about energy is true? A. Energy is a wave. B. Energy cannot travel through a vacuum. C. Energy has the ability to cause motion. D. Energy cannot change form.
Answers
Answer:
C.
Explanation:
There is such thing a wave energy, but that doesn't quite fit for this question. B. I have not heard of that, so it has to be incorrect. C. Yes, energy can cause motion in a lot of ways. D. Energy can change forms so that is incorrect.
Explain
applications
MRI
X-ray
Ultrasound
Infrared Radiation
Answers
Answer and Explanation:
--> MRI (Magnetic Resonance Imaging) is an imaging technique that involves the use of radio waves and magnetic field to generate high detailed images of the human body. It's clinical applications includes:
• Bone and joint MRI: these are done to check for bone and joint problems such as bone marrow disorders, arthritis, or bone tumours.
• A Spine MRI: This is used to investigate the spinal disc and innervations for disorders such as spinal tumours.
• Chest MRI: This is used to detect abnormalities of the heart, heart valves and coronary arteries.
--> X-RAY: These are electromagnetic waves of short wavelength with high penetrating power. They are produced when fast moving electrons strike a mass of heavy atoms such as those of metals. It's applications includes:
• They are used to detect hidden cracks in materials.
• They are used to show broken bones in human body.
• They are used in the study of internal structures of crystals.
• In agriculture, x-rays are used in killing germs.
--> ULTRASOUND: This makes use of high frequency sounds to detect abnormalities in the human body. An ultrasound machine transmits sound waves into the body which are reflected at the surfaces between the tissues of different density. It can also be used in different disciplines such as imaging, cleaning, mixing, navigation and communication It's applications includes:
•. Detection of Cracks: when applied on metallic surface under investigation, high frequency sound wave reflects back which and be predicted and recorded.
--> INFRARED RADIATION: This is a type of electromagnetic radiation with wavelength longer than visible light. It is visible to the human eye and most heated surfaces transmits infrared radiation. It's applications includes:
• it is used for the purpose of sensing and detection. For example the night vision goggles and infrared cameras. Remote control makes use of infrared light waves to change channels in the television.
Two spheres of equal mass, A and B, are projected off the edge of a 1.0 m bench. Sphere A has a horizontal velocity of 10 m/s and sphere B has a horizontal velocity of 5 m/s.
__ 5. If both spheres leave the edge of the table at the same instant, sphere A will land
a. at some time after sphere B.
b. at the same time as sphere B.
c. at some time before sphere B.
d. There is not enough information to decide.
__ 6. If both spheres leave the edge of the table at the same instant, sphere A hits the floor at the spot marked X. Sphere B will hit the floor
a. at some point between the edge of the table and X.
b. at some point past X.
c. at the same distance from the table as X.
d. there is not enough information to decide.
Answers
Answer:
c. because A will land first becuase its heavier
and D.
Explanation:
you are driving at 18m/s down Lyndale avenue. A car backs out a driveway 25 meters in front of you. You continue at that speed while your brain processes the danger which takes 0.25 seconds. You then slam on the brakes and your car has an acceleration of -5.4m/s^2. Do you stop before reaching the driveway(and hitting the car)? Show your work. This is a two-part problem with constant speed and braking.
Answers
Hello!
For this, first let's calculate time of stop:
t = (V - Vi) / a
Replacing:
t = (0 m/s - 18 m/s) / -5,4 m/s^2
Resolving:
t = -18 m/s / -5,4 m/s^2
t = 3,33 s + 0,25 s = 3,58 s
Now lets calculate distance traveled, with formula:
d = Vi*t + (a*t^2)/2
Replacing:
d = 18 m/s * 3,58 s + (-5,4 m/s^2 * (3,58 s)^2) /2
Resolving:
d = 64,44 m + (-34,604 m)
d = 29,83 m
Then, the vehicle will CRASH
give an example of a normal force. type below.
Answers
Normal force is the force exerted when an object is on an surface. So an example could be a pile of books on top of a table.
Which term best describes the motion of the rope particles in relation to the motion of the rope wave shown in the photograph
Answers
Answer:
A: Perpendicular
Explanation:
The question is incomplete as it lacks the image of the rope wave motion.
However, as found on "estudyassistant", the options are;
A) Perpendicular
B) Circular
C) Longitudinal
D) Parallel
From all that, we can say that;
The rope's are moving simultaneously in the same pattern without touching each other.
This is therefore a mechanical wave being created with the motion having oscillations that are perpendicular to the direction of energy transfer of the ropes.
This is a definition of transverse waves because the rope particle motion is perpendicular to the wave motion.
Answer:
A: Perpendicular
Explanation:
Read above explanation.
2.14x10^-7. What is the answer. Write in standered form
Answers
Look at this model of an atom. Where are the electrons located and how many are there?
Answers
Answer:
The electrons are on the outer shell, there are 10 of them.
Explanation:
There are two in the inner shell and eight in the outer shell, giving us a total of 10 electrons
What is the main difference between analog anddigital technology?a. Digital technology reproduces sound more faithfullythan analog technology.b. Analog technology stores information as soundwaves; digital technology stores it as strings of onesand zeroes.c. Analog technology can be used to record sound andimages; digital technology can only be used to recordsound.d. Analog technology is based on binary code; digitaltechnology is based on electromagnets
Answers
Answer:
Answer b)
Explanation:
The correct answer is that analog technology stores information as sound-waves, while digital technology stores it as strings of ones and zeroes. So pick answer b)