A professional boxer hits his opponent with a 1035 N horizontal blow that lasts 0.175 s. The opponent's total body mass is 120 kg and the blow strikes him near his center of mass and while he is motionless in midair. Determine the following.(a) The opponent's final velocity after the blow(b) Calculate the recoil velocity of the opponent's 5.0-kg head if hit in this manner, assuming the head does not initially transfer significant momentum to the boxer's body.

Answers

Answer 1

Answer:

(a) vf = 1.51 m/s

(b) vf = 36.22 m/s

Explanation:

The rate of change of momentum is equal to the force:

[tex]F = \frac{mv_f-mv_i}{t}[/tex]

[tex]Ft = m(v_f-v_i)[/tex]

where,

F = Force = 1035 N

t = time = 0.175 s

vi = initial speed = 0 m /s

vf = final speed = ?

(a)

m = mass of body = 120 kg

Therefore,

[tex](1035\ N)(0.175\ s)=(120\ kg)(v_f - 0\ m/s)\\\\v_f = \frac{181.125\ Ns}{120\ kg} \\\\[/tex]

vf = 1.51 m/s

(b)

m = mass of head = 5 kg

Therefore,

[tex](1035\ N)(0.175\ s)=(5\ kg)(v_f - 0\ m/s)\\\\v_f = \frac{181.125\ Ns}{5\ kg} \\\\[/tex]

vf = 36.22 m/s


Related Questions

A swift blow with the hand can break a pine board. As the hand hits the board, the kinetic energy of the hand is transformed into elastic potential energy of the bending board; if the board bends far enough, it breaks. Applying a force to the center of a particular pine board deflects the center of the board by a distance that increases in proportion to the force. Ultimately the board breaks at an applied force of 870 N and a deflection of 1.4 cm.
a. To break the board with a blow from the hand, how fast must the hand be moving? Use 0.50 kg for the mass of the hand.
b. If the hand is moving this fast and comes to rest in a distance of 1.2 cm, what is the average force on the hand?

Answers

Answer:

A. The hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand = 1025 N

Explanation:

A.To determine the speed the hand must move with to break the board, the force workdone in breaking the board is found first.

Workdone = force × distance

Minimum force required = 870 N;

Distance moved by board/Deflection in order to break = 1.4 cm = 0.014 M

Workd done = 870 N × 0.014 m = 12.18 Nm or 12.18 J

This work done = Kinetic energy of the hand

Kinetic energy = mv²/2 ; where m is mass and v is velocity

Mass of hand = 0.50 Kg, velocity = ?, K.E. = 12.18 J

v² = 2 KE/m

v = √2KE/m

v = √(2 × 12.18/0.50)

v = 6.98 m/s

Therefore, the hand must move with a velocity of 6.98 m/s to break the board.

B. Average force on the hand

This can be determined using the equation of motion, v² = u² + 2as to find acceleration, since force = mass × acceleration

From the equation of motion, a = v² - u²/2s

At rest, v = 0, u = 6.98, s = 1.2 cm = 0.012 m

a = 0² - 6.98²/ 2 × 0.012

a = -2030 m/s²

Force = 2030 m/s² × 0. 50 kg = 1015 N

Therefore, Average force on the hand = 1025 N

the oscillation of pendulum is ...... motion​

Answers

Answer:

A simple pendulum consists of a ball (point-mass) m hanging from a (massless) string of length L and fixed at a pivot point P. When displaced to an initial angle and released, the pendulum will swing back and forth with periodic motion.

Verify that your equation has the masses and the velocities before and after the collision. Solve equation for the initial velocity of the projectile, Vo. As the bob swings upward from h1 to a max of h2, what is happening to the kinetic energy of the system?

Answers

Answer:

Decrease occur in kinetic energy.

Explanation:

The kinetic energy decreases when the the Bob swings reaches to the maximum height because the motion of the bob slower down. At maximum height, the kinetic energy decreases whereas the value of potential energy is the highest. The main reason of higher potential energy is that it depends on height of an object while on the other hand, kinetic energy depends on the motion of an object so that's why the value of kinetic energy decreases and potential energy increases at maximum height of the bob.

Una persona en la tierra tiene una masa de 70[kg]. Calcule: a) Su fuerza peso en la tierra. b) Su fuerza peso en la luna (considere que la aceleración gravitatoria en la luna es de 1.62 [m/s²]) *

Answers

Answer:

a. El peso = 686 Newton

b. El peso = 113.4 Newton

Explanation:

Dados los siguientes datos;

Masa = 70 kg

Aceleración debida a la gravedad en la luna = 1,62 m/s² una.

a. Para encontrar la fuerza-peso en la Tierra;

Sabemos que la aceleración debida a la gravedad es igual a 9,8 m/s² en el planeta Tierra.

El peso se puede definir como la fuerza que actúa sobre un cuerpo o un objeto como resultado de la gravedad.

Matemáticamente, el peso de un objeto viene dado por la fórmula;

[tex] Peso = mg [/tex]

Dónde;

m es la masa del objeto.

g es la aceleración debida a la gravedad.

Substituting into the formula, we have;

El peso = 70 * 9.8

El peso = 686 Newton

b. To find weight on moon;

Weight = mass * acceleration due to gravity on moon

Weight = 70 * 1.62

Weight = 113.4 Newton

You have been hired to design a spring-launched roller coaster that will carry two passengers per car. The car goes up a 13-m-high hill, then descends 20 m to the track's lowest point. You've determined that the spring can be compressed a maximum of 2.4 m and that a loaded car will have a maximum mass of 430 kg. For safety reasons, the spring constant should be 13 % larger than the minimum needed for the car to just make it over the top. Part A What spring constant should you specify

Answers

Answer:

22.15 N/m

Explanation:

As we know potential energy = m*g*h

Potential energy of spring = (1/2)kx^2

m*g*h = (1/2)kx^2

Substituting the given values, we get -  

(400)*(9.8)*(10) = (0.5)*(k)*(2.0^2)

k = 39200/2.645

k = 19600 N/m

For safety reasons, this spring constant is increased by 13 % So the new spring constant is  

 k = 19600 * 1.13 = 22148 N/m = 22.15 N/m

A car of mass 500 kg is moving at a speed of 1.2 m/s. A man pushes the car,
increasing the speed to 2 m/s. How much work did the man do?
A. 640 J
B. 360 J
C. 1360 J
D. 1000 J

Answers

The answer is D I’m not really sure yet

Work done by  man will be A. 640 J

What is work energy theorem?

The work-energy theorem states that the net work done by the forces on an object equals the change in its kinetic energy.

according to work energy theorem

Work done = final Kinetic energy - initial kinetic energy

                   = KE (final) - KE (initial )

                   = 1/2 m ([tex]v^{2}[/tex])  - 1/2 m ([tex]u^{2}[/tex])

                  = 1/2 m ([tex]v^{2}[/tex] - [tex]u^{2}[/tex])

                  = 1/2 * 500 * ( [tex]2^{2}[/tex] - [tex]1.2^{2}[/tex])

                  = 250 * 2.56 = 640 J

correct answer is A. 640 J

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(d) A glass prism made from a material of refractive index 1.86 has a refracting angle of 60. The prism is immersed in a water of refractive index 1.33. Determine the minimum deviation for a parallel beam of light transversing the prism

Answers

Answer:

The angle of minimum deviation is 28.72°

Explanation:

u welcome

Mỗi giây có 2,1.1018 ion+
2 và 1,8.1018
electron chạy qua tiết diện đèn ống.
Đường kính tiết diện của đèn ống là 2,0
cm. Mật độ dòng điện trung bình qua
đèn là bao nhiêu

Answers

A I seen it on the quiz

Two parallel conducting plates are separated by 10.0 cm, and one of them is taken to be at zero volts. (a) What is the electric field strength between them, if the potential 8.00 cm from the zero volt plate

Answers

Complete Question

Two parallel conducting plates are separated by 10.0 cm, and one of them is taken to be at zero volts. (a) What is the electric field strength between them, if the potential 8.00 cm from the zero volt plate(and 2.00 cm from the other) is 450 V?

Answer:

[tex]V'=562.5v[/tex]

Explanation:

From the question we are told that:

Separation distance [tex]d=10cm[/tex]

Voltage at 8cm [tex]V_8=450v[/tex]

Generally the equation for Voltage is mathematically given by

[tex]|V|=|E.d|[/tex]

Where

E=electric field

Therefore

At [tex]d=0.8[/tex]

 [tex](450-0)V=E*(0.08m)[/tex]

 [tex]E=\frac{450}{0.08}[/tex]

 [tex]E=5625v/m[/tex]

Therefore

 At [tex]d=10[/tex]

 [tex]V'=Ed[/tex]

 [tex]V'=5625*0.1m[/tex]

 [tex]V'=562.5v[/tex]

advantages of 2 pulley system​

Answers

Answer:

Using multiple pulleys decreases the amount of force necessary to move an object by increasing the amount of rope used to raise the object. The mechanical advantage (MA) of a pulley system is equal to the number of ropes supporting the movable load.

QUESTION 24
2 point
A man travels 40 km eastwards, then 40 km to the south before finally travelling
10 km west. At the end of his journey the magnitude of his displacement is

Answers

-30. 40 east on timeline, 40 down, then 10 over right

The formula to convert oF to oC =5/9( F -32)

Answers

I’m sorry ⟟ can’t help with this one

A supernova is a large explosion that takes place at the end of a star's life cycle. Although supernovas only burn for a short amount of time, they can tell scientists a lot about the universe. Scientists use electromagnetic waves to detect supernovas. Why are electromagnetic waves used instead of sound waves?
A. Electromagnetic waves are created by physical vibrations.
B. Electromagnetic waves travel slower than sound waves.
C. Electromagnetic waves can travel in vacuums.
D. Electromagnetic waves cannot be absorbed.

Answers

I’m pretty sure it’s c

Electromagnetic waves can travel in vacuums.

To find the correct statement among all the options, we need to know more about the electromagnetic wave.

What is electromagnetic wave?Electromagnetic wave is a transeverse wave in which both the electric field and magnetic field travel simultaneously.The electric field and magnetic field are perpendicular to each other and perpendicular to the direction of prapagation of the EM wave.How is the electromagnetic wave created?

Electromagnetic wave is created from the oscillation of any charge particles like electron, proton, ions etc. .

What is the speed of electromagnetic waves?The speed of electromagnetic wave in vacuums is maximum that is 3×10⁸ m/s. (Speed of EM wave is much more than that of sound (340m/s)).In any other medium, its speed changes and it depends on the refractive index of that medium.How is the electromagnetic wave affected by medium?In any medium, the electromagnetic wave is absorbed to some extent except ideal vacuum. Also in vacuum in space, it's absorbed; because the vacuum in space is not completely vacuum since it contains few molecules per cubic kilometers.However, the electromagnetic wave can travel in any medium even in vacuum while the sound wave can travel only in particle medium.

Thus we conclude that scientists use electromagnetic waves to detect supernovas because electromagnetic waves can travel in vacuums.

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What is the direction of a vector with an x component of -12 m and a y component of -15 m?

Answers

Answer:

[tex]51.34^{\circ}[/tex]

Explanation:

Given that,

x component of a vector = -12 m

The y component of a vector = -15 m

We need to find the direction of a vector. The direction of a vector is given by :

[tex]\tan\theta=\dfrac{y}{x}[/tex]

Put all the values,

[tex]\tan\theta=\dfrac{-15}{-12}\\\\\theta=\tan^{-1}(\dfrac{-15}{-12})\\\\\theta=51.34^{\circ}[/tex]

So, the direction of vector is [tex]51.34^{\circ}[/tex] to x component.

A student solving a physics problem to find the unknown has applied physics principles and obtained the expression: μkmgcosθ=mgsinθ−ma, where g=9.80meter/second2, a=3.60meter/second2, θ=27.0∘, and m is not given. Which of the following represents a simplified expression for μk?A student solving a physics problem to find the unknown has applied physics principles and obtained the expression: , where , , , and is not given. Which of the following represents a simplified expression for ?tanθ− agTo avoid making mistakes, the expression should not be simplified until the numerical values are substituted.gsinθ−agcosθThe single equation has two unknowns and cannot be solved with the information given.

Answers

Solution :

Given expression :

[tex]$\mu_k$[/tex]mgcosθ = mgsinθ − ma

Here, g = 9.8 [tex]m/s^2[/tex] , a = 3.60 [tex]m/s^2[/tex] , θ = 27°

Therefore,

[tex]$\mu_k mg \cos \theta = mg \sin \theta - ma$[/tex]

[tex]$\mu_k mg \cos \theta = m(g \sin \theta - a)$[/tex]

[tex]$\mu_k g \cos \theta = (g \sin \theta - a)$[/tex]

[tex]$\mu_k =\frac{(g \sin \theta-a)}{g \cos \theta}$[/tex]

Mow calculating the coefficient of kinetic friction as follows :

[tex]$\mu_k=\frac{g \sin \theta-a}{g \cos \theta}$[/tex]

[tex]$\mu_k=\frac{9.8 \times \sin 27^\circ-3.60}{9.8 \times \cos 27^\circ}$[/tex]

[tex]$\mu_k=0.097$[/tex]

equations of kinematics new dimensions

Answers

Answer:

Δx Displacement

t Time interval

v0  Initial velocity

v  Final velocity

a  Constant acceleration

Explanation:

I dont know if this helps because these are kinda like, examples... hope it helps tho :)

define force and types of force​

Answers

Answer:

Force is the strength or weight of things that depends on movement. The types of forces are conteact force, spring force, applied force, air resistance force, normal force, frictional force, tension force, and non-contact force.

If we use 1 millimeter to represent 1 light-year, how large in diameter is the Milky Way Galaxy?

Answers

Answer:

if 1 light year was one millimeter then 105,700 light years = 105,700 mm, (or 105.7 meters in case you needed to simplify or something)

On a day when the speed of sound is 345 m/s, a 440 Hz tuning fork causes a tube closed at one end to vibrate in the second harmonic. How long is the tube?​

Answers

Answer:

Length = 3.136 meters

Explanation:

Given the following data;

Speed = 345 m/s

Frequency = 440 Hz

To find how long is the tube;

First of all, we would determine the wavelength;

Wavelength = speed/frequency

Wavelength = 345/440

Wavelength = 0.784 m

Next, we would determine how long is the tube using the formula;

[tex] Length = \frac {2n - 1}{4} * wavelength [/tex]

Substituting into the formula, we have;

[tex] Length = \frac {2*1 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {2 - 1}{4} * 0.784 [/tex]

[tex] Length = \frac {1}{4} * 0.784 [/tex]

Length = 3.136 meters

What is the y component of a vector that is 673 m at -38o?

Answers

Answer:

D_y = 414.38m

Explanation:

D_y = D*sin(x)

D_y = 673m*sin(38°)

D_y = 414.38m

Speed of light in water

Answers

Answer:

225,000 kilometers per second

Explanation:

Have a nice day

Khối lượng ban đầu của mặt trời m⊙ = 2 × 1030 kg trong đó có 71 % là
hydrogen. Trong 5×10^9 năm đầu tiên, mặt trời phát ra năng lượng với công suất
3.86 × 10^26 W, nhờ phản ứng
4p → 4+2He + 2e
+ 2νe + 26 MeV
trong đó bốn proton tổng hợp thành hạt α và tỏa ra năng lượng 26 MeV. Hãy
xác định
a) số hạt proton của mặt trời tại thời điểm ban đầu.
b) số hạt proton của mặt trời tham gia phản ứng trong 1 năm.
c) số hạt proton còn lại trong mặt trời sau 5 × 10^9 năm.
d) thời gian để tiêu thụ hết 10 % số hạt proton còn lại của mặt trời

Answers

Answer:

jsgssbvwsvs

Explanation:

ifmd understand

Certain rifles can fire a bullet with a speed of 950 m/s just as it leaves the muzzle (this speed is called the muzzle velocity). The muzzle is 75.0 cm long and the bullet is accelerated uniformly from rest within it. What is the acceleration (in {g}'s) of the bullet in the muzzle? If, when this rifle is fired vertically, the bullet reaches a maximum height {H}, what would be the maximum height (in terms of H) for a new rifle that produced half the muzzle velocity of this one?

Answers

Answer:

a) By [tex]v^2 = u^2 + 2as[/tex] => a= 70291.70.

(b)By [tex]v = u + at[/tex] => t= 1.58 ms.

(c)By [tex]v^2 = u^2 - 2gh[/tex] => H = 46045.92 m.

Explanation:

a) By [tex]v^2 = u^2 + 2as[/tex]

[tex](950)^2 = 0 + 2 \times a \times 0.75\\a = 601666.67 m/s^2\\a/g = 688858.70/9.8 = 70291.70[/tex]

(b)By [tex]v = u + at[/tex]

[tex]950 = 0 + 601666.67 \times t\\t = 1.58 x 10^-3 sec = 1.58 ms[/tex]

(c)By [tex]v^2 = u^2 - 2gh[/tex]

[tex]0 = (950)^2 - 2 \times9.8 \times H\\H = 46045.92 m[/tex]

While riding his bike through a neighborhood, Joe notices a red sign out of
the corner of his eye. He quickly comes to a stop. Which active reading
strategy is he using?
A. Asking questions
B. Making mental images
C. Summarizing
D. Using visual cues
SUBMIT

Answers

Answer:

B

Explanation:

because it take to the thought of a situation

Answer:

d i think

Explanation:

and are u using IXL???

We say that evaporation is a cooling process. (a) What cools and what warms? We say that condensation is a warming process. (b) What warms and what cools?

Answers

Answer:

a liquid warms gas cools

b solid piece warms and liquid cools

Two stars that are in the same constellation:

Answers

Answer:

A binary star is a star system consisting of two stars orbiting around their common barycenter.

❣️(◍Jess bregoli◍)❣️

#keep learning

Consider the heaviest box of 150 lb that you can push at constant speed across a level floor, where the coefficient of kinetic friction is 0.45, and estimate the maximum horizontal force that you can apply to the box. A box sits on a ramp that is inclined at an angle of 60.0° above the horizontal. The coefficient of kinetic friction between the box and the ramp is 0.45.
If you apply the same magnitude force, now parallel to the ramp, that you applied to the box on the floor, what is the heaviest box (in pounds) that you can push up the ramp at constant speed? (In both cases assume you can give enough extra push to get the box started moving.)

Answers

I really don’t know can I see a picture of the question so I can see clear

Maximum horizontal force that can be applied on the box is 300.32 N.

Mass of the heaviest box that can be pushed on the ramp at constant speed is 105.16 pound.

What is meant by kinetic friction ?

Kinetic friction is defined as the opposing force exerted by the surface on an object in contact with it, when there is relative motion between the two surfaces.

Here,

Mass of the box, m = 150 lb = 68.1 kg

Coefficient of kinetic friction, μ = 0.45

Maximum horizontal force that can be applied on the box is the kinetic frictional force. Frictional force,

F(k) = μmg

F(k) = 0.45 x 68.1 x 9.8

F(k) = 300.32 N

Now, the box sits on a ramp inclined at 60°

Coefficient of kinetic friction, μ = 0.45

The net force here acting on the box placed in the ramp is due to the kinetic frictional force and the weight of the box.

So,

Frictional force, F(k)' = μmgcosθ

F(k)' = 0.45 x M x 9.8 x cos 60

F(k)' = 2.2M

Weight of the box acting horizontally,

W = Mgsinθ

W = M x 9.8 x sin60

W = 8.5M

Therefore, net force,

Fn = W - F(k)'

Fn = 8.5M - 2.2M

Fn = 6.3M

The total force acting on the box is

F = F(k) - Fn

ma = 300.32 - 6.3M

Since, the box is moving with constant speed, the acceleration, a = 0

Therefore,

300.32 - 6.3M = 0

6.3M = 300.32

M = 300.32/6.3

M = 47.7 kg = 105.16 pound

Hence,

Maximum horizontal force that can be applied on the box is 300.32 N.

Mass of the heaviest box that can be pushed on the ramp at constant speed is 105.16 pound.

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what are parasites? Give some example​

Answers

Answer:

parasites are creatures the gain benefit off of other animals usually harming them eg:ticks on dogs

HELP ME PLSSSS!!!!!!!
Which statement describes why the viscosity of olive oil is higher than that of
rubbing alcohol?
A. The molecules that make up olive oil are longer than those that
make up alcohol, so they have more resistance to sliding past one
another.
B. The molecules that make up olive oil repel one another, while the
molecules that make up alcohol are attracted to one another.
C. The molecules that make up olive oil are shorter than those that
make up alcohol, so they have more resistance to sliding past one
another.
D. The molecules that make up olive oil are attracted to one another,
while the molecules that make up alcohol repel one another.

Answers

Answer:B

Explanation: The answer explains it

The molecules that make up olive oil are longer than those that make up alcohol, so they have more resistance to sliding past one another. The correct answer is option A.

This higher resistance to flow leads to a higher viscosity in olive oil compared to rubbing alcohol. Viscosity is a measure of a fluid's resistance to flow, and longer molecules in olive oil result in stronger intermolecular forces and entanglements. In contrast, rubbing alcohol has shorter and less complex molecules, which allow them to move more freely and exhibit lower viscosity. The molecular structure and intermolecular forces play a crucial role in determining the viscosity of liquids, making olive oil more viscous than rubbing alcohol. Option A is correct.

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A car traveling at 14 m/s accelerates at 3.5 m/s² for 5 seconds. How much distance does it travel during that time?​

Answers

Answer: 113.75

Explanation:

You know

acceleration = a = 3.5 m/s²

time = t = 5 seconds

initial velocity = u = 14 m/s

Unknown is distance = s = ?

Use equation: s = ut + [tex]\frac{1}{2}[/tex] at²

Substitute all the known values inside the equation:

s = (14*5) + 0.5 * 3.5 * 5²

s = 70 + 43.75 = 113.75 m

The car travels 113.75 metres.

Other Questions
which statement is accurate? A. Jim Crow laws took effect during the Civil War. B. Jim Crow laws were created before Reconstruction. C. Jim Crow laws were created as a response to the Civil Rights Act. D. Jim Crow laws took effect after ratification of the 14th Amendment Line segment Q R , Line segment R S and Line segment S Q are midsegments of WXY.Triangle R Q S is inside triangle X Y W. Point R is the midpoint of side X Y, point S is the midpoint of side Y W, and point Q is the midpoint of side X W. The length of Q R is 2.93 centimeters, the length of R S is 2.04 centimeters, and the length of Q S is 2.28 centimeters.What is the perimeter of WXY?11.57 cm12.22 cm12.46 cm14.50 cm I don't even know what we are working on at this point so if this isnt biology, sorry. The decorative features of Shang bronze ritual vessels were inspired by __________. (HeLp hOomAnZ i iZ neEdS uR HelPinG :V)What compromise was made by the South in 1790 that changed the location of the nations capital?a. The North would allow the federal government to collect taxes.b. The national capital would later be moved north to Philadelphia.c. The North would repay its own war debt.d. The South agreed the federal government would take over the war debt owed by the states. The measure of degrees CAGIGISO Very short answer questions. 1. How do you define human development? (a)What is the meaning of subsidiary company (2) write a paragraph on tarak Mehta ka ulta chasma Your city has a sales tax rate of 6%. If you just spent $30 on sales tax, how much were your purchases? Nagpur is famous for its (a) apple (b) pineapple (c) oranges What did Hernn Corts do after the Aztec emperor Montezuma II welcomed him to Tenochtitln?A) He took the emperor captive.B) He burned his own ships.C) He met with Atahualpa.D) He encountered the Pacific Ocean. consider the figure below FREE BRAINLIST TO WHOMEVER ANSWERS THIS QUESTION! - Write me a 7 sentences comparing and contrasting Juneteenth celebrations with 4th of July celebrations. No plagiarism please! Need answer ASAP pls its important a. What is Art Exhibition?b. State any four benefits of exhibitionc. Describe four essential steps in planning exhibition 20. Find the measure of < DEG. (G.CO.C.10)4EA. 25B. 8(3y + 4) A (5y-10)C. 30DFClick to add speaker notese here to searchOc3PO.a Th th no lin kt vi mt phn t ngoi mng t bo, hot ho mt protein kinase bn trong t bo? Which function can represent the height, y, of the railing in inches according to the horizontal distance in inches, x, from the top of the stairs? y = StartFraction 3 Over 4 EndFractionx + 36 y = 3x + 36 y = StartFraction 3 Over 4 EndFractionx + 36 y = 3x + 36 discribe 2 different types of bird nests and list their forms and functions