Answer:
The correct option is;
11.95
Explanation:
The given parameters are;
The height from which the rock is dropped = 700 meters
The time for the to hit the ground is given by the relation, h = u·t + 1/2·g·t²
Where;
h - The height = 700 meters
u = The initial velocity = 0
t = The time taken for the rock to cover the height, h, and hit the ground
g = The acceleration due to gravity = 9.81 m/s²
Therefore, we have by substitution,
700 = 0 × t + 1/2 × 9.81 × t²
∴ t = √(700/(1/2 × 9.81)) ≈ 11.95
The time for the rock to hit the ground, t ≈ 11.95 seconds.
(8th grade HELP)
1. Inertia causes a stationary object to...
a.stay still
b.move
c.have an increased velocity
d.change it’s speed or direction
2. Once an applied force causes an object to start moving, the object keeps moving because....
a.none of the above
b.the force continues to be applied to it
c.no other force is acting on it
d.it has inertia
A stone dropped from the top of a 80m high building strikes the ground at 40 m/s after falling for 4 seconds. The stone's potential energy with respect to the ground is equal to its kinetic energy
Answer:
A
Explanation:
Given that a stone dropped from the top of a 80m high building strikes the ground at 40 m/s after falling for 4 seconds. The stone's potential energy with respect to the ground is equal to its kinetic energy. (use 9 - 10 m/s)
O at the moment of impact
2 seconds after the stone is released after the stone has fallen 40 m
when the stone is moving at 20 m/s
At the top of the hill, the P.E = mgh
P.E = 10 × 80 × m
P.E = 800m
At the moment of impact, K.E = 1/2mv^2
K.E = 1/2 × 40^2 × m
K.E = 1/2 × 1600 × m
K.E = 800m
Since both P.E and K.E are the same, we can therefore conclude that the stone's potential energy with respect to the ground is equal to its kinetic energy at the moment of impact.
The correct answer is option A.
Electromagnetic radiation is emitted by accelerating charges. The rate at which energy is emitted from an accelerating charge that has charge q and acceleration a is given by dEdt=q2a26πϵ0c3 where c is the speed of light.Part AIf a proton with a kinetic energy of 5.0 MeV is traveling in a particle accelerator in a circular orbit with a radius of 0.530 m , what fraction of its energy does it radiate per second?(dE/dt)⋅1sE =
Answer:
P /K = 1,997 10⁻³⁶ s⁻¹
Explanation:
For this exercise let's start by finding the radiation emitted from the accelerator
[tex]\frac{dE}{dt}[/tex] = [tex]\frac{q^{2} a^{2} }{6\pi \epsilon_{o} c^{2} }[/tex]
the radius of the orbit is the radius of the accelerator a = r = 0.530 m
let's calculate
\frac{dE}{dt} = [(1.6 10⁻¹⁹)² 0.530²] / [6π 8.85 10⁻¹² (3 108)³]
P= \frac{dE}{dt}= 1.597 10⁻⁵⁴ W
Now let's reduce the kinetic energy to SI units
K = 5.0 10⁶ eV (1.6 10⁻¹⁹ J / 1 eV) = 8.0 10⁻¹⁹ J
the fraction of energy emitted is
P / K = 1.597 10⁻⁵⁴ / 8.0 10⁻¹⁹
P /K = 1,997 10⁻³⁶ s⁻¹
A rollercoaster car has 2500 J of potential energy and 160 J of
kinetic energy at the top of the first hill.
How much energy and what kind of energy will there be at the
bottom of the first hill?
2660 J of KE
0 2660 J of Peg
2500 J of KE
160 J of PEG
Answer:
E_{k2}=2660 [J] kinetic energy.
Explanation:
The energy in the initial state i.e. when the rollercoaster is at the top is equal to the energy in the final state i.e. when it is at the bottom of the hill.
These states can be represented by means of the second equation.
[tex]E_{k1}+E_{p1}=E_{k2}\\160 + 2500 = E_{k2}\\E_{k2}=2660 [J][/tex]
Since the rollercoaster is located in the bottom of the hill where the potential energy level is zero, therefore there is only kinetic energy in the second state.
Which of the following is an example of adhesion?
What are the forces that resist motion that make Newton's 1st Law hard to completely visualize on Earth?
20POINTS, this is not free, answer ASAP
Best answer gets BRAINLIEST
Answer: Well it's not sinking. It is also not flooring or floating. so my guess it must be rising up.
Explanation: When something is impacted, the pressure of the force of energy is released and lands directly on a other object. So what does Jell-O do when you shake it? It wobbles right? what happens when you put your hand in a bucket of water? It makes the water rise up. So That's why I think it is rising up.
Answer:
Rising up because the weight of the object depends on the water and mass
Explanation:
Karla Ayala pulls a sled on an icy road (dangerous!). Because of Karla's pull, the tension force is 151 N, and the rope makes a 20.0° with the horizontal. If the 7.0-kg sled is pulled across 10.0 meters, what is the work done by Karla?
Answer:
W = 1418.9 J = 1.418 KJ
Explanation:
In order to find the work done by the pull force applied by Karla, we need to can use the formula of work done. This formula tells us that work done on a body is the product of the distance covered by the object with the component of force applied in the direction of that displacement:
W = F.d
W = Fd Cosθ
where,
W = Work Done = ?
F = Force = 151 N
d = distance covered = 10 m
θ = Angle with horizontal = 20°
Therefore,
W = (151 N)(10 m) Cos 20°
W = 1418.9 J = 1.418 KJ
Hi......
............
Answer:
Heyy!
Explanation:
..********************
Which TWO of the following examples are a chemical reaction?
A melting ice
B breaking glass
C crumpling paper
D rusting iron
E burning wood
Answer:
D and E
Explanation:
They both produce a new object or substance afterwards.
Answer:
D. and E.
Explanation:
Hope this helps and I hope u have an Amazing day!!
If a 50kg boulder is 100m off the ground and a 25 kg boulder is 100 m off the ground, which has a
stronger gravitational force pulling it towards Earth?
Answer:
Explanation:
It 100 kg It think
PLS HELP which ones would be made of cells? and which ones show cell walls?
Cork, Sponge, Wood, Plastic, Tree
The first question's answer depends on what you mean by "sponge". If you're talking about sea sponges, then all but plastic are made up of cells. Some sponges used for cleaning are also made of plant material but also other, non-organic materials like dyes.
Cell walls are only present in plant cells, so they would be found in cork (derived from a certain tree bark), wood, and trees. Synthetic sponges made with plant material might also contain them, but they wouldn't be made entirely of cells with walls.
From given options or choices all are made up of cells except plastic and among the other four Cork, Sponge, Wood, and tree all show cell walls except Sponge.
A cell is the basic structural unit of all living organisms and contains various cell organelles. On the base of different cell organelles or presence or absence of the certain organelles help in distinct and divide the cell type.
The major types of cells are:
Prokaryotic cellsEukaryotic cellsPlastic is not a living organism as there are no cells and is made up of polymers of hydrocarbon.
The cell wall is one of the major cellular structures that helps in identifying the type of cell organism and protects the organism from the external environment. It classifies the organism on its constituent of the cell wall.
In eukaryotic cells, animal cells have no cell wall, however, fungi cells, plant cells have a cell wall. A sponge is an animal and other cork wood, and trees are plants or plant-based products.
Thus, the sponge does not show the cell wall.
Learn more about the cell wall:
https://brainly.com/question/18662393
PLEASE HELP ME! IM TIMED
Answer:
the third one
Explanation:
the 1991 eruption of mt. pinatubo was the scariest in history
Answer:
C
Explanation:
It is based on someone’s experience and how they felt about the accident
Biker 1 is on a motorcycle facing West is initially at rest. The motorcycle speeds up from rest to 25 mph in three seconds.
Biker 2 is right by his side to start. He speeds up from rest to 85 mph in eight seconds.
Which biker has a greater acceleration?
Biker 1's acceleration:
(25 mph) / (3 s) = ((25 mi/h) • (1/3600 h/s)) / (3 s) ≈ 0.00231 mi/s²
Biker 2's acceleration:
(85 mph) / (8 s) = ((85 mi/h) • (1/3600 h/s)) / (8 s) ≈ 0.00295 mi/s²
Biker 2 has the greater acceleration.
Ball A, moving towards the right, collides with
stationary ball B. Ball A bounces back; B moves
off slowly to the right. Which has the greater
mass, A or B?
Answer:
ball b has the greater mass.
Explanation:
b only moved because a bumped into it. if a bounced back, it had less mass and b moved slowly.
A rock has a mass of 3.1 kg. What is its weight on earth
Answer:
W = 30.38 N
Explanation:
Given that,
Mass of a rock, m = 3.1 kg
We need to find the weight of the rock on the surface of Earth. Weight of an object is given by :
W = mg
g is the acceleration due to gravity, g = 9.8 m/s²
W = 3.1 kg × 9.8 m/s²
= 30.38 N
So, the weight of the rock on the Earth is 30.38 N.
PLEASE HELP ME! IM TIMED
Answer: tectonic plates
Explanation:
PLEASE HELP
is lighting firecrackers a form of conduction, convention, or radiation
Answer:
Convection
Explanation:
conduction is like, electricity. radiation is like using a microwave.
Answer:
conduction
Explanation:
recall that conduction is the transfer of heat between objects that come in direcr contact.
You are putting heat directly on the part of the firework that allows it to spark, therefore it is conduction.
Convection takes place within a fluid.
Radiation is indirect heat through waves. (think of the sun warming us indirectly)
Question 12 of 20
How does decreasing the length of a wire affect a circuit?
A. It reduces the resistance caused by the wire.
B. It reduces the voltage carried by the wire.
O C. It increases the resistance caused by the wire.
D. It increases the current passing through the wire.
If we decrease the length of the wire in a circuit, It reduces the resistance.
What is resistance?Resistance is the opposition offered to the flow of current by a circuit element. The factors that affect resistance include;
Length of the wireCross sectional area of the wireHence, if we decrease the length of the wire in a circuit, It reduces the resistance caused by the wire since the resistance depends on the length of the wire.
Learn more about resistance: https://brainly.com/question/15067823
Answer: A
Explanation:
a 5 kg object is pushed with a 10 n force for 1 second how much will the momentum of the object change?
Answer:
5 kg m/s
Explanation:
Because you need 5 N to push a 5 kg object so 5 will be left over
A steel beam is rotated in a horizontal plane to provide the centripetal acceleration for training pilots. If the pilot sits 2.19 m from the center of rotation, at what speed must he rotate in order to experience a horizontal centripetal acceleration of 65.8 m/s/s?
Given :
Pilot sits 2.19 m from the center of rotation.
Horizontal centripetal acceleration is 65.8 m/s².
To Find :
The angular velocity of the pilot .
Solution :
We know, centripetal acceleration is given by :
[tex]a = \omega^2 r\\\\\omega = \sqrt{\dfrac{a }{r}}\\\\\omega = \sqrt{\dfrac{65.8 }{2.19}}\\\\\omega = 5.48\ s^{-1}[/tex]
Hence, this is the required solution.
Which physical property is best measured using only a balance? A. Density B. Volume C. Color D. Mass
Answer:
D. Mass
hope it helps
Explanation:
Mass is commonly measured with a balance
Please help which one !!
Answer:
4th one
Explanation:
Someone please tell me the answer with working please!! I
A rock hits a window and stops in 0.15 s. The net force on the rock is 58 N during the collision. What is the magnitude of the change in momentum of the rock?
Answer:
8.7kgm/s
Explanation:
Change in momentum=force×time
Diana hangs a lead cylinder with a force of 12 N from a model bridge.
Which vector(s) accurately illustrates the reaction force of the bridge on the lead cylinder?
The action and reaction law allows us to find that the reaction force, the weight of the cylinder, is:
12 N force directed upward
Newton's third law or action and reaction law, establishes that if two bodies interact with each other the force that one applies to the other, is equal in magnitude to the force of the second on the first but in the opposite direction, that is, all forces act in pairs one in each body that interact.
Forces with these characteristics are called action and reaction.
In this case we have a hanging cylinder, with the cylinder it has mass so the weight is 12 N it acts on the table in a downward direction, let's say this is the action force.
In response to this force, the table exerts a force on the cylinder of equal magnitude but in the opposite direction, which is why it is directed upwards.
let's analyze the force diagram
When analyzing the forces shown in the diagram, the forces of equal magnitude to the weight are the first twoThe weight is directed downward, the answer must be directed upward.
In conclusion using theaction and reaction law we find that the answer for reaction force is:
12 N force directed upward
Learn more about the action and reaction law here:
https://brainly.com/question/22746565
How do you compare the mass of proton, neutron, and
electron?
Answer:Explanation:
Protons and neutrons have very similar mass, while electrons are far lighter, approximately 11800 times the mass. Protons are positively charged, neutrons have no electric charge, electrons are negatively charged. The size of the charges is the same, the sign is opposite.
Integrated science please help ASAP!...
Answer:
SewageAgricultural pollutionOilRadioactive substanceRiver dumpingMarine dumpingLittering trash Industrial wasteMining activitiesChemical fertilizersExplanation:
I hope this helps
Carbon is stored in leaves in various forms, such as sugar. When leaves decay, they lose mass. Which of the following sentences explains what happens to the carbon that is stored in leaves when they decay?
a. The carbon evaporates.
b. The carbon is destroyed as the leaves decompose.
c. The carbon is converted into nitrogen by bacteria in the soil.
d. The carbon is converted into carbon dioxide and released into the atmosphere.
Answer:either D or C
Explanation:
The carbon is converted into carbon dioxide and released into the atmosphere. therefore the correct answer is option D
What is a Chemical compound?A chemical compound is a combination of two or more either similar or dissimilar chemical elements, for example, H₂O is a chemical compound made up of two oxygen atoms and a single hydrogen atom.
These chemical compounds are formed because of different types of bonds between the constituent's elements, the chemical bonds are mainly ionic bonds, covalent bonds,s, and hydrogen bonds.
Carbon is stored in leaves in various forms, such as sugar. When leaves decay, they lose mass.
The carbon is converted into carbon dioxide and released into the atmosphere is the sentence that explains what happens to the carbon that is stored in leaves when they decay.
Thus, the carbon is converted into carbon dioxide and released into the atmosphere. the correct answer is option D.
Learn more about a chemical compound from here
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Question in the photo
Answer:
a lever that is what is used