What must be the reaction force when someone hits a tree with an axe?

What Must Be The Reaction Force When Someone Hits A Tree With An Axe?

Answers

Answer 1

Answer: The correct option is that the axe handle applying a force to the person's hand.

Explanation:

This reaction force is due to Newton's third law of motion. This law states that for every action there is equal and opposite reaction to it. This implies that when a force is being exerted on a surface, the surface must exert a force that is equal and opposite in direction to the exerting force. This law represents a certain symmetry in nature that forces always occur in pairs, and one body cannot exert a force on another without experiencing a force itself.

A typical example of Newton's third law includes:

--> When you hit a tree with an axe: with your hand you exert a force on the tree with the intention to cut it down(action force). The same force you excreted on the tree would be felt in your hands (reaction force).

--> when air rushes out of a balloon: when air escapes for a balloon, the opposite reaction is that the balloon flies up.


Related Questions

Please help (I didn’t know what subject to put this in but it’s earth science)

Answers

Spring summer and USA for the first 2
2. The answer is USA! https://www.netweather.tv/weather-forecasts/news/10277-tornado-facts-which-countries-have-the-most-and-the-deadliest-tornadoes

I think 1. Is A.

3. F5

4. A.

A uniform, solid sphere of radius 2.50 cm and mass 4.75 kg starts with a purely translational speed of 3.00 m/s at the top of an inclined plane. The surface of the incline is 2.75 m long, and is tilted at an angle of 22.0∘ with respect to the horizontal. Assuming the sphere rolls without slipping down the incline, calculate the sphere's final translational speed v2 at the bottom of the ramp.

Answers

Answer:

The final translational seed at the bottom of the ramp is approximately 4.84 m/s

Explanation:

The given parameters are;

The radius of the sphere, R = 2.50 cm

The mass of the sphere, m = 4.75 kg

The translational speed at the top of the inclined plane, v = 3.00 m/s

The length of the inclined plane, l = 2.75 m

The angle at which the plane is tilted, θ = 22.0°

We have;

[tex]K_i[/tex] + [tex]U_i[/tex] = [tex]K_f[/tex] + [tex]U_f[/tex]

K = (1/2)×m×v²×(1 + I/(m·r²))

I = (2/5)·m·r²

K =  (1/2)×m×v²×(1 + 2/5) = 7/10 × m×v²

U = m·g·h

h = l×sin(θ)

h = 2.75×sin(22.0°)

∴ 7/10×4.75×3.00² + 4.75×9.81×2.75×sin(22.0°) = 7/10 × 4.75×[tex]v_f[/tex]² + 0

7/10×4.75×3.00² + 4.75×9.81×2.75×sin(22.0°) ≈ 77.93

∴ 77.93 ≈ 7/10 × 4.75×[tex]v_f[/tex]²

[tex]v_f[/tex]² = 77.93/(7/10 × 4.75)

[tex]v_f[/tex] ≈ √(77.93/(7/10 × 4.75)) ≈ 4.84

The final translational seed at the bottom of the ramp, [tex]v_f[/tex] ≈ 4.84 m/s.

6. 15. A boy takes 5 seconds to reach each point from ‘A’ to ‘B’, ‘B’ to ‘C’ and ‘C’ to ‘D’ as
shown in the diagram. If AB = BC = CD = 20 m then which of the following information is
correct when the boy reaches point D from point A via BC?

Answers

Explanation:

Could you also show the diagram

5. Which one of the following factors is directly proportional to density of liquid? (a) Temperature (b) Volume of liquid (c) Upthrust (d) Density of object

Answers

Answer:

A

The upthrust on a floating body is in upwards direction and is equal to the weight of the liquid displaced

B

The upthrust is directly proportional to the density of the liquid in which the solid is immersed

C

The upthrust is directly proportional to the volume of the fluid displaced by a solid

The upthrust acts on the body in upward direction at the center of buoyancy.

Upthrust is equal to the weight of liquid displaced by object and weight of liquid will depend on its density.

Upthrust is F=Vρg ,where V is the volume of liquid displaced and ρ is the density of fluid.

The total lateral pressure acting on an immersed object on one side is equal and in opposite direction to the total lateral pressure acting on the other side.

You toss an apple across the room to a friend. Which of the following statements is true about the apple at the top of its trajectory?
A. Its acceleration is zero.
B. The horizontal component of its velocity is zero.
C. The vertical component of its velocity is 9.8 m/s down.
D. Its acceleration is 9.8 m/s2 down.​

Answers

B is the correct answer!! The horizontal component of its velocity is zero.

Solve for M₂

Base Equation: M₂ = Fr²/GM₁

F = 132N, G = 6.67 x 10⁻¹¹ Nm²/kg², r = .243m, and M₁ = 1.175 x 10⁴ kg, then what is M₂ = ?

Answers

Explanation:

M₂ = Fr²/GM₁

M₂ = [(132N)(.243m)²]/[(6.67*10^-11N*m²/kg)(1.175*10^4kg)]

M₂ = (7.79N*m²)/(7.84*10^-7N*m²)

M₂ = 9.94*10^6 kg

Joseph jogs from one end A to the other end B of a straight 300 m road in 2 minutes 30 seconds and then turns around and jogs 100 m back to point C in another 1 minute. What are Joseph's average speeds and velocities in jogging (a) from A to B and (b) from A to C?​

Answers

Answer:

Explanation:

(a) It is given that Joseph jogs on a straight road of 300m in a time interval of 2 minutes and 30 seconds, which is equal to 150seconds. Therefore, when Joseph jogs from point A to point B, he covers a distance of 300m in time of 150seconds. Hence, his average speed is 300m/150s=2ms^−1. Since it is a straight road and he jogs in a single direction in this case, his displacement is equal to 300m. Since it is a straight road and he jogs in a single direction in this case, his displacement is equal to 300m.

Hence, his average velocity is 300m/150s=2ms^−1

(b) Then it is given that he turns back and points B and jogs on the same road but in the opposite direction for a time interval for 1 minute and covers a distance of 100m.If we consider the whole motion of Joseph, i.e. from point A to point C, then he covers a total distance of 300m+100m=400m. And he covers this total distance in a time interval of 2.5min+1min=3.5min=210s.

Therefore, his average speed for this journey is 400m210s=1.9ms−1.

For the same journey is displacement is equal to the distance between the points A and C,i.e. 300m−100m=200m.

Hence, his average velocity for this case is 200m/210s=0.95ms^−1

A flat, circular, copper loop of radius r is at rest in a uniform magnetic field of magnitude B that extends far beyond the edge of the loop. The plane of the loop is parallel to the page and the magnetic field is directed perpendicular to and out of the page, as indicated by the blue dots. If the magnitude of the magnetic field is decreased at a rate of 1 T/s, what is true about the induced current in the copper loop

Answers

Answer:

     i =[tex]- \frac{r \ A'}{2 \ rho}[/tex] ,  i =  0.92   A

Explanation:

This exercise asks for the electromotive force, which can be calculated with Faraday's law

          fem = [tex]- \frac{d \Phi_B }{dt}[/tex]

where the magnetic flux

          Ф = B. A

bold letters indicate vectors. We can write this equation

          Ф = B A cos θ

In this case the magnetic field is perpendicular to the page and the normal to the loop of the loop is also parallel to the page, therefore the angle is zero and the cosine is 1

the loop is

          A = π r²

we substitute in the first equation

          fem = - π r² [tex]\frac{dB}{dt}[/tex]

we substitute the values

          fem = -π r² 1

          fem = - π r²

to calculate the current let's use ohm's law

           V = i R

            R = ρ L / A'

where A 'is the area of ​​the wire and L is the length of the loop

            L = 2π r

           

            V = i (ρ 2π r / A ')

            I = [tex]\frac{V \ A'}{2\pi \ r \ rho}[/tex]

         

In this case

           V = fem

 

           I = fem / R            

           i =[tex]- \frac{r \ A'}{2 \ rho}[/tex]

         

In order to complete the calculation, you need the radius of the loop and / or the wire cutter.

if we assume that the loop has a radius of r = 1 cm = 0.01 m and an area of ​​the wire   A'= π 10⁻⁶ m²   a radius of the wire 1 mm

           i = - 10⁻² π 10⁻⁶ / ( 2 1.7 10-8)

           i =  0.92   A

Describe the laws of liquid pressure and Explain the term fluid. (Please give the correct answer, it's really urgent)​

Answers

Answer:

The laws of liquid pressure are  

(i) Pressure inside the liquid increases with the depth from the free surface of the liquid.

(ii) Pressure is same at all points on a horizontal plane, in case of stationary liquid.

(iii) Pressure is same in all directions about a point inside the liquid.

(iv) Pressure at same depth is different in different liquids. It increases with the increase in the density of the liquid.

(v) A liquid will always seek its own level.

A Fluid is any liquid or gas or generally any material that cannot sustain a tangential, or shearing, force when at rest.  

Explanation:

Which property do the elements in each column of the representative elements series of the periodic table have in common?(1 point)

number of neutrons
number of orbitals
number of valence electrons
number of protons

Answers

The property that the elements in each column of the representative elements series of the periodic table have in common is: number of valence electrons.

An atom can be defined as the smallest unit comprising of matter that forms all chemical elements. Thus, atoms are basically the building blocks of matters and as such determines or defines the structure of a chemical element.

Generally, atoms are typically made up of three distinct particles and these are protons, neutrons and electrons.

Periodic table is an organized tabular array of all the chemical elements arranged in order of increasing atomic number (in rows).

Valence electrons can be defined as the number of electrons present in the outermost shell of an atom. Valence electrons are used to determine whether an atom or group of elements found in a periodic table can bond with others. Thus, this property is typically used to determine the chemical properties of elements.

In the periodic table, chemical elements that are having the same number of valence electrons are found in the same column.

This ultimately implies that, all the chemical elements such as Hydrogen, Sodium, etc., with one (1) valence electrons in their outermost shell (S-orbital) are found in the first (1st) column of the periodic table.

In conclusion, property that the chemical elements in each column of the representative elements series of the periodic table have in common is number of valence electrons.

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Part B After producing electricity in many different ways, describe what causes electricity to flow in the coil? In your response, describe the types of forces acting on the electrons and how they result in movement.

Answers

Explanation:

If a coil of wire is placed in a changing magnetic field, a current will be induced in the wire. ... A changing magnetic field through a coil of wire therefore must induce an emf in the coil which in turn causes current to flow.

Due to the flow of the current run, the coil magnetic field is produced. Magnetic fields result in magnetic force.

What is electric force?

The electric force between the two charges is directly propotional to the product of the charge and inversly propotional to the square of the distance between them.

A current will be generated in a wire coil if it is put in a changing magnetic field. As a result, a changing magnetic field through a coil of wire must create an emf in the coil, causing the current to flow.

A current is induced in a coil of wire when it is put in a changing magnetic field. Something generates an electric field that drives the charges around the wire, causing the current to flow.

Hence due to the flow of the current in the coil magnetic field is produced.

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why do the other animals listen to old major speak in the barn late on night?​

Answers

https://brainly.com/question/19388823

Hope this helps!

Robin fired a bullet of mass 100 gm from a gun of mass 5 kg. The bullet leaves the gun with a speed of 400 m/s. After penetrating 4 cm of a plank of 10 cm, the bullet loses one third of its initial velocity.
a. Calculate the backward velocity of the gun?
b. Can the bullet penetrate the plank of the wood completely? Explain mathematically.

please help

Answers

(a) The recoil or backward velocity of the gun is 8 m/s.

(b) The bullet cannot penetrate the plank of the wood completely.

The given parameters include;

mass of the bullet, m₁ = 100 g = 0.1 kgmass of the gun, m₂ = 5 kginitial velocity of the bullet, u₁ = 400 m/sthickness of the plank, x = 10 cm

(a) The backward or recoil velocity of the gun is calculated by applying the principle of conservation of linear momentum.

let the backward or recoil  velocity of the gun = u₂

m₁u₁  + m₂u₂ = 0

m₂u₂ = -m₁u₁

[tex]u_2 = -\frac{m_1u_1}{m_2} \\\\u_2 = - \frac{0.1 \times 400}{5} \\\\u_2 = -8 \ m/s[/tex]

Thus, the recoil or backward velocity of the gun is 8 m/s.

(b) determine if the bullet can penetrate the plank of the wood completely

the bullet traveled 4 cm and lost ¹/₃ of u₁the remaining distance to completely penetrate the plank = 6 cmthe final velocity of the bullet at 4 cm, v = 400 - ¹/₃ x 400 m/s  = 266.67 m/s

the acceleration of the bullet is calculated as;

v² = u₁² + 2as

2as = v² - u²

[tex]a = \frac{v^2 -u_1^2}{2s} \\\\a = \frac{(266.67)^2 -(400)^2}{2\times 0.04} = -1.111 \times 10^6 \ m/s^2[/tex]

Finally, determine the distance traveled by the bullet when it comes to a complete stop, that is the final velocity = 0

[tex]v_f^2 = v^2 + 2ad\\\\2ad = v_f^2 - v^2\\\\d = \frac{v_f^2 - v^2}{2a} \\\\d = \frac{(0) - (266.67)^2}{2(-1.111\times 10^6)} \\\\d = 0.032 \ m[/tex]

d = 3.2 cm

The total distance traveled by the bullet inside the plank = 4 cm + 3.2 cm = 7.2 cm

Therefore, the bullet cannot penetrate the plank completely.

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A bike travels at 3.0 m/s, and then accelerates to a speed of
8.5 m/s in a time of 2.5 seconds. The average acceleration of
the bike is
m/s2

Answers

The average acceleration of the bike is 2.2 m/s²

What is average acceleration?

Acceleration, rate at which velocity changes with time, in terms of both speed and direction.

A point or an object moving in a straight line is accelerated if it speeds up or slows down.

According to the question,

Given, initial velocity, u=3.0m/s and final velocity v=8.5 m/s

Time = 2.5 seconds

If a be the acceleration.

a = [tex]\frac{v-u}{t}[/tex]

a = [tex]\frac{8.5 - 3.0}{2.5s}[/tex]

⟹ a=2.2 m/s²

So, The average acceleration of the bike is 2.2 m/s²

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An airplane starts from rest and undergoes a uniform acceleration of 10.8 m/s^2 for 16.7 s seconds before leaving the ground. What is its displacement?

Answers

Answer:

3012.012m

Explanation:

s=it +1/2(10.8)(16.7)^2

valancy of an atom is +2. what does it mean. ​

Answers

Answer: I hope you find it useful

Explanation: Group 2 elements have two valence electrons. The two valence electrons are easily lost in the formation of chemical bonds. Once the two electrons are lost, the atom then has a full outer shell and is therefore more stable.

so,  if an atom has valency 2 , then it means that the atom can combine with 2 other atoms .

Which are characteristics of a prokaryotic cell? Select three options.


O contains DNA

O lacks DNA

O contains ribosomes

O lacks ribosomes

O contains a nucleus

O lacks a nucleus

I NEED THIS QUICKLY

Answers

Answer:

A. Contains DNA

C. Contains ribosomes

F. Lacks a nucleus

Explanation:

Derive the following equations. :a=u-v by t​

Answers

here is the answer!

mercury is commonly used in thermometer give reasons​

Answers

Answer:

hi

BECAUSE MERCURY IS USED BECAUSE IT is the only liquid available in room temperature

Explanation:

pls mark as a BRAINLIST

please help me with my question I will like and mark as brainliest for the first correct answer due tomorrow morning​

Answers

Answer:

1845.26 ?

Explanation:

18.46 × 99.96= 1845.2616 = 1845.26

im not entirely sure though

Mercury is used in thermometer.Give reason​

Answers

Answer:

Mercury is the only one in liquid state at room temperature

A 20 kg truck drives in a circle of radius 4 m at 10m/s. What causes
the circular motion?
A. Normal Force
B. Friction
C. Tension
D. Gravity

Answers

Answer:

Normal force

Explanation:

The force is centipetral force

Calculating :-

Mass=m=20kgRadius=r=4mVelocity=10m/s=v

We know

[tex]\boxed{\sf F_c=\dfrac{mv^2}{r}}[/tex]

[tex]\\ \sf\longmapsto F_c=\dfrac{20(10)^2}{4}[/tex]

[tex]\\ \sf\longmapsto F_c=\dfrac{20(100)}{4}[/tex]

[tex]\\ \sf\longmapsto F_c=\dfrac{2000}{4}[/tex]

[tex]\\ \sf\longmapsto F_c=500N[/tex]

An imaginary star is four light years from earth. The star has a planet, upon which a large mirror has been installed. The mirror faces earth. A ten year old boy aims his telescope at the mirror. How old will the boy be when he sees his own reflection?

Answers

Answer:

14 years

Explanation:

because the light will take four years to reach the earth. And the star is four light years away from the earth.

Hope that helps you please follow

An imaginary star is four light years from earth. The star has a planet, upon which a large mirror has been installed. The mirror faces earth. A ten year old boy aims his telescope at the mirror,then the boy would be 14 years old when he will see his own reflection.

What is a light year?


It can be defined as the distance travelled by the light in one year .it is represented in units of distance such as miles or km.

1 light year is calculated by multiplying the speed of light with the time of one year

1 light year = speed of light × one year time period

1 light year = 3×10⁸ ×(365×24×60×60)

                  =9.461× 10¹⁵ meter


As given in the problem 10 year old boy aims his telescope at the mirror which is 4 light years away then the light has to travel four years to reach the boy ,then the boy would be 14 year old when he would see his own reflection.
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A person has power of 550 watt. What does it mean? ​

Answers

Answer:

It means that person can do work or can posses energy at a rate of 550 watts.

Or : can posses energy of 550 joules in one second.

Explanation:

[tex]{ \bf{power = \frac{work}{time} }}[/tex]

e. write unit of the following physical quantities

Answers

Answer:

electric current=ampere(A)

force=Newton (N)

area=metres square(m^2)

power=watt(w)

density=kg/m3 

amount of substance =mole per cubic meter (mol/m3).

volume=cubic meter (m3),

Answer:

thanks for brainlist brother.........

a busis moving with the initial velocity 10m/s . after 4 seconds, the velocity becomes 30m/s . find the acceleration produce by bus,......please I need help​

Answers

Answer:

5 m/s²

Explanation:

Use the acceleration formula: [tex]a=\frac{v_f-v_i}{t}[/tex]

a = acceleration (m/s²)vf = final velocity (m/s)vi = initial velocity (m/s)t = time (s)

Based on the information given to us by the prompt, we know:

vi = 10 m/svf = 30 m/st = 4 s

Substitute these values for the variables to calculate the acceleration:

[tex]a=\frac{30-10}{4}\\\\a=\frac{20}{4}\\\\a=5[/tex]

Therefore, the acceleration of the bus is 5 m/s².

5. Tại sao khi lặn ta luôn cảm thấy tức ngực và càng lặn sâu thì cảm giác tức ngực càng tăng? A. Ap suất của nước giảm ​​B. Ap suất không khí tăng C. Ap suất không khí giảm ​​D. Ap suất của nước tăng

Answers

Answer:

c and d

Explanation:

obviously kksxsxksxkskxkskxksxksxsxsxsxsxsxsxs

A stone is thrown into a pond. Five waves were made from the same source in 10 seconds.

Answers

The frequency of the wave for the stone thrown in the pond is 0.5Hertz.

The question does not specify what to calculate but we can look for the frequency of the wave.

Frequency is the number of oscillations completed in one second. This is interpreted as:

x oscillations = 1second

If Five waves were made from the same source in 10 seconds for a stone that is thrown inside the pond, then:

5 oscillations = 10seconds

Divide both expressions to get x (the required frequency)

x/5 =1/10

Cross multiply

10x = 5

Divide both sides by 10

10x/10 = 5/10

x = 1/2

x = 0.5Hertz

Hence the frequency of the wave is 0.5Hertz.

NB: The period of the wave is simply the reciprocal of the frequency.

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An empty cardboard box falls from a high platform. Through the use of special equipment it was found that the energy of the cardboard box at the top of the fall was more than the energy of the box at the bottom of the fall. Explain.

Answers

Answer:

The mechanical energy of the cardboard box, M.E. = K.E. + P.E.

Where;

P.E. = The potential energy of the cardboard box = m·g·h

K.E. = The kinetic energy of the cardboard box = (1/2)·m·v²

Where;

m = Mass of the cardboard box

g = The (constant) acceleration due to gravity ≈ 9.81 m/s²

h = The height of the cardboard box

v = The velocity of the cardboard box

At the top of the fall, where h = The height of the platform = [tex]h_{platform}[/tex], and v = 0 (the box is initially at rest at the top), the M.E. is given as follows;

[tex]M.E._{top}[/tex] = P.E. + K.E. = m·g·[tex]h_{platform}[/tex] + (1/2) × m × 0² = m·g·[tex]h_{platform}[/tex]

However, at the bottom of the fall, the height of the box, h = 0, the velocity of the box, v = 0, therefore, the total energy at the bottom, after the box comes to rest, [tex]M.E._{bottom}[/tex] = 0

Therefore;

The total energy of the box at the top of the fall, .[tex]M.E._{top}[/tex] = m·g·[tex]h_{platform}[/tex] was more than the total energy of the box at the bottom of the fall,

[tex]M.E._{bottom}[/tex] = 0

Explanation:

difference between uniform motion and non uniform motion

Answers

Answer:

Uniform motion is a type of motion that is characterized as the motion of an object wherein the object moves in a straight line and its velocity remains unchanged along that line, regardless of the duration of time, as it occupies equal distances at equal time interval and Non-uniform motion is described as the motion of an object wherein the object moves at different speeds and does not cover the same distance at equal time intervals, regardless of the duration of the time interval.

Answer:

hope it's help you

Explanation:

In Uniform motion, the movement of a body is along the straight line with constant speed. In non uniform motion, the movement of a body is along the straight line with variable speed. In uniform motion, the body covers equal distance in an equal interval of time.

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