Một vô lăng sau khi bắt đầu quay được một phút thì thu được vận tốc 700
vòng/phút. Tính gia tốc góc của vô lăng

Answers

Answer 1
yes, I’ll join ur zoom,

Related Questions

I NEED HELP WITH THIS PLEASE

Answers

Answer:

D

Explanation:

One of the factors of increasing the rate of a reaction is increasing concentration. Therefore adding more people increases the number of people on the dance floor , therefore increasing the concentration increases the rate of reaction.

A 7.5-kg rock and a 8.9 × 10-4-kg pebble are held near the surface of the earth. (a) Determine the magnitude of the gravitational force exerted on each by the earth. (b) Calculate the magnitude of the acceleration of each object when released.

Answers

Answer:

F' = 73.7 N

F = 8.749×10⁻³ N

a' = a =  9.83 m/s²

Explanation:

(a)

For the rock

Applying

F' = Gm'm/r²................... Equation 1

Where F = magnitude of the gravitational force on the rock, G = Gravitational constant, m' = mass of the rock, m = mass of the earth, r = radius of the earth.

From the question,

Given: m' = 7.5 kg

Constant: m = 5.98×10²⁴ kg, G = 6.67×10⁻¹¹ Nm²/kg², r = 6.37×10⁶ m

Substitute these values into equation 1

F' = 6.67×10⁻¹¹ (7.5)(5.98×10²⁴)/(6.37×10⁶)²

F' = 7.37×10¹ N

F' = 73.7 N

Also, For the pebble,

F = GMm/r².............. Equation 2

Where M = mass of the pebble, F = Gravitational force exerted on the pebble by the earth

Given: M = 8.9×10⁻⁴ kg,

Substitute into equation 2

F = 6.67×10⁻¹¹(8.9×10⁻⁴)(5.98×10²⁴)/(6.37×10⁶)²

F = 8.749×10⁻³ N

(b)

For the rock,

a' = F'/m'

Where a' = magnitude of the acceleration of the rock

a' = 73.7/7.5

a' = 9.83 m/s²

For the pebble,

a = F/M

Where a = acceleration of the pebble

a = (8.749×10⁻³)/(8.9×10⁻⁴)

a = 9.83 m/s²

a man is standing near the edge of a cliff 85 meters high. he throws a stone upward vertically with an intial velocity of 10 m/s. the stone clears the cliff edge on the way down and falls all the way to the ground. what is the maximum height of the stone above the ground

Answers

Answer:

h = 90.10 m

Explanation:

Given that,

A man is standing near the edge of a cliff 85 meters high, h₀ = 85 m

The initial speed of the stone, u = 10 m/s

The path followed by the projectile is given by :

[tex]h(t)=-4.9t^2+10t+85[/tex] ....(1)

For maximum height,

Put dh/dt = 0

So,

[tex]\dfrac{dh}{dt}=-9.8t+10=0\\\\t=\dfrac{10}{9.8}\\\\=1.02\ s[/tex]

Put the value of t in equation (1).

[tex]h(t)=-4.9(1.02)^2+10(1.02)+85\\\\=90.10\ m[/tex]

So, the maximum height of the stone is equal to 90.10 m.

a mass of air occupied 150 cm3 at 20°c and 760 mmhg pressure. calculate it volume when heated to 100°c and constant pressure​

Answers

Answer:

191 cm³

Explanation:

We'll begin by converting celsius temperature to Kelvin temperature. This can be obtained as follow:

T(K) = T(°C) + 273

Initial temperature (T₁) = 20 °C

Initial temperature (T₁) = 20 °C + 273

Initial temperature (T₁) = 293 K

Final temperature (T₂) = 100 °C

Final temperature (T₂) = 100 °C + 273

Final temperature (T₂) = 373 K

Finally, we shall determine the final volume of the air. This can be obtained as follow:

Initial volume (V₁) = 150 cm³

Initial temperature (T₁) = 293 K

Final temperature (T₂) = 373 K

Pressure = constant

Final volume (V₂) =?

V₁/T₁ = V₂/T₂

150 / 293 = V₂ / 373

Cross multiply

293 × V₂ = 150 × 373

293 × V₂ = 55950

Divide both side by 293

V₂ = 55950 / 293

V₂ ≈ 191 cm³

Thus, the final volume of the air is 191 cm³

Lighting is the movement of?

Answers

Explanation:

Movement:refers to the changing in the lights whether it be a change in intensity, color or direction of origin.

calculate the correct fuse that should be used for a 230V,1KW electric hair dryer.​

Answers

Answer: 4 A

Explanation:

Given

Voltage [tex]V=230\ V[/tex]

Power [tex]P=1\ kW[/tex]

Power is given by [tex]P=VI\\[/tex]

Insert the values

[tex]\Rightarrow 1000=230\times I\\\\\Rightarrow I=\dfrac{1000}{230}\\\\\Rightarrow I=3.84\ A[/tex]

The rating of fuse is slightly higher than the normal operating conditions. Therefore, a 4 A fuse should be used here.

With neat circuit diagrams where possible show any two (2) ways of direct current motor
excitations,

Answers

Mainly there are two types of DC Motors. One is Separately Excited DC Motor and other is Self-excited DC Motor. The self-excited motors are further classified as Shunt wound or shunt motor, Series wound or series motor and Compound wound or compound motor. The dc motor converts electrical power into mechanical power.

___________________ uses the heat energy from the Earth. This type of alternative energy can be installed basically anywhere in North Carolina.
A) wave energy
B) solar energy
C) nuclear energy
D) geothermal energy

Answers

Answer:

Geothermal!!

Explanation:

Geo means earth! Just like Hydro means water, and Pyro means fire :)

Answer:

The Answer is D). Geothermal energy

Explanation:

Hope this helps!!!!!

Communication satellite use__sent by a transmitting station to transmit signals over long distances A microwaves B polar waves C light D radio waves

Answers

D: radio waves

Explanation:

radio wves are use to carry satellite signals

an object is 70 um long and 47.66um wide. how long and wide is the object in km?​

Answers

Answer:

length =  7*10^(-8)km

width = 4.666*10^(-8) km

Explanation:

We know that:

1 μm = 1*10^(-6) m

and

1km = 1*10^3 m

or

1m = 1*10^(-3) km

if we replace the meter in the first equation, we get:

1 μm = 1*10^(-6)*1*10^(-3) km

1 μm = 1*10^(-6 - 3)km

1 μm = 1*10^(-9)km

Now with this relationship we can transform our measures:

Length: 70 μm is 70 times 1*10^(-9)km, or:

L = 70*1*10^(-9)km = 7*10^(-8)km

And for width, we have 47.66um, this is 46.66 times 1*10^(-9)km, or:

W = 46.66*1*10^(-9)km = 4.666*10^(-8) km

Bola bermassa 200 gram dilempar
ke bawah dari ketinggian 20 m
dengan kecepatan 2 m/s. Jika
percepatan gravitasi bumi 10
m/s2 energi kinetik pada
ketinggian 8 m adalah ......​

Answers

Answer:

0.4

Explanation:

[tex] \frac{1}{2} mv ^{2} [/tex]

kinetic energy formula , potential energy is not considered

0.5×0.2×2×2

figure 2. sketch of bar and magnetic field lines observations PLEASE HELPPPP ​

Answers

Hope this sketch helps

The tires of a car make 60 revolutions as the car reduces its speed uniformly from 95.0 km/h to 60.0 km/h. The tires have a diameter of 0.88 m. If the car continues to decelerate at this rate, how far does it go

Answers

Answer:

-2.869 rad/s2

Explanation:

Data given:

speed, vi at 95.0 km/h = 95 X (1 hour /3600 seconds) X (1000m / 1km)

Note that, for every 1 hour, there will be 60sec X 60sec = 3600 seconds

And for every 1km, there will be 1000m.

So, speed of 95.0 km/h = 26.389 m/s

speed, vi  =  r ω (radius X angular velocity)

 angular velocity, ωi = v/r

ωi = 26.389  m/s ÷ half of 0.88 m diameter

= 59.975 rad/s

decelerating to speed, vf at 60.0 km/h = 60 X X (1 hour /3600 seconds) X (1000m / 1km)

= 16.667m/s

The angular velocity for this speed = 16.667m/s ÷ half of 0.88 m diameter

 = 37.879rad/s

 How far the car goes is equivalent to the angular acceleration which equals to (ωf^2 - ωi^2) ÷ 2θ

= (37.879rad/s)^2 - (59.975 rad/s)^2 ÷ 2 (60 rev X 2π rad/rev)

= -2.869 rad/s2

what is the suitable way of using social media​

Answers

Answer:

not using it too much and getting addicted

Explanation:

Don’t used everyday or you will be addicted to it, just used when it’s necessary

15. Muous produced by snails help them move along the ground How does the mucus help maits
move?
A Mucus is cold
C. Mucus reduces friction
B. Mucus leaves a trail D. Mucus makes the snail lighter
16. Which of the following statements does NOT tell about the effects of pravitational force
on objects?
A. The more distant the body from the earth, the lesser is the gravitational force of attraction
B. Gravitational force pushes the objects upward
C. Gravitational force is greater when the objects are closer together
D. The farther you are from earth, the lesser your weight
17. Why is it difficult for us to go up in a mountain than go down?
A We are moving against gravity
B. We are pulled by the wind
C. We are moving towards gravity
D. None of the above
18. Which of these will have the strongest gravitational pull on Earth'?
A a baby
C. a drinking glass
B. a half sack of nice
D. an elephant
19. Without air resistance, all objects fall at the same rate.
D. Neither True or False
C Maybe
B. False
20. The gravity between two objects increases as the distance between them
D stabilizes
C neutralizes
B. increases
A. decreases
A True​

Answers

Answer:

15.C Mucus reduces friction

PLEASE HELP ME WITH THIS ONE QUESTION

Answers

Answer:

[tex]^{214} _{83} Bi[/tex]  → [tex]^{210}_{81}Tl[/tex] + [tex]^4_2He[/tex]

Explanation:

[tex]^{214} _{83} Bi[/tex]  → [tex]x[/tex] + [tex]^4_2He[/tex]

Subtract the [tex]^4_2He[/tex] from the [tex]^{214} _{83} Bi[/tex]

214 - 4 = 210

83 -2 = 81

Therefore, [tex]x[/tex] = [tex]^{210}_{81}Tl[/tex]

Find the weight of a man whose mass is 40 kg on earth.


(also
write complete data plus proper formula).



Answers

I am sure it help you with that much ☺️

Explanation:

pleasae give me some thanks please good morning sister

A small block, with a mass of 0.05 kg compresses a spring with spring constant 350 N/m a distance of 4 cm. It is released from rest, then slides around the loop and up the incline before momentarily comes to rest at point A. The radius of the loop is 0.1 m.

Required:
Find the elastic potential energy.

Answers

Answer:

The elastic potential energy of the spring is 0.28 J

Explanation:

Given;

mass of the block, m = 0.05 kg

spring constant, k = 350 N/m

extension of the spring, x = 4 cm = 0.04 m

The elastic potential energy of the spring is calculated as;

[tex]U_x = \frac{1}{2}kx^2\\\\U_x = \frac{1}{2} \times 350 \times (0.04)^2\\\\U_x = 0.28 \ J[/tex]

Therefore, the elastic potential energy of the spring is 0.28 J

Mention & Instrument used to measure
the mass of the body.

Answers

Answer:

a scale is used to measure the mass of the body

An air-filled parallel-plate capacitor has plates of area 2.90 cm2 separated by 2.50 mm. The capacitor is connected to a(n) 18.0 V battery.

Answers

Complete question:

An air-filled parallel-plate capacitor has plates of area 2.90 cm2 separated by 2.50 mm. The capacitor is connected to a(n) 18.0 V battery. Find the value of its capacitance.

Answer:

The value of its capacitance is 1.027 x 10⁻¹² F

Explanation:

Given;

area of the plate, A = 2.9 cm² = 2.9 x 10⁻⁴ m²

separation distance of the plates, d = 2.5 mm = 2.5 x 10⁻³ m

voltage of the battery, V = 18 V

The value of its capacitance is calculated as;

[tex]C = \frac{k\epsilon_0A}{d} \\\\C = \frac{(1)(8.85\times 10^{-12})(2.9 \times 10^{-4})}{2.5 \times 10^{-3}} \\\\C = 1.027 \times 10^{-12} \ F[/tex]

Therefore, the value of its capacitance is 1.027 x 10⁻¹² F

2 Lights slows down when it enters water from air.
a What happens to its speed?
b What happens to its wavelength?
c What happens to its frequency?​

Answers

Light travels as waves, with the wavefronts perpendicular to the direction of motion. In the animation shown here, the wavefronts are represented by the green parallel lines. The red arrow represents the direction of motion. As light moves from air into water, it not only slows, but the wavelength changes. wavelength becomes shorter in the denser medium of water.


Light will travel in straight line unless it meets any object (medium) in its path. Light changes its speed when it passes from one medium to other and the direction of light changes. This bending of light is called refraction.

This will happen in both when light passes through lighter to denser medium and also while comes from denser medium to lighter medium.

The speed of the light is increases when it comes from denser to less dense medium and decreases when it passes through lighter to denser. Light travels faster in vacuum compared with any other medium.

Refractive index defines the speed of light in a medium.

Refractive index (n)= v1/v2, v1 and v2 are the speed of light in vacuum and medium, respectively.

More the refractive index, slower the speed of light in that medium.

Coming to the wavelength of light, λ=v / f and here the frequency (f) of incident will not change when light passes through different medium.

Wavelength is directly proportional to the speed (v), then the wavelength increases if speed of light increases and vice versa.

The wavelength of light decreases when it goes from air to water because the speed of light decreases.

Mark brainliest

what are 2 ways that we can express to show our connection to our culture

Answers

Answer:

Food, clothes, language, and belief

Hot water is added to three times its water at 10 degree Celsius and the resulting temperature at 20 degree Celsius. what is the initial temperature ​

Answers

50 degrees Celsius is the answer
50 dibdbsis ddjdjendd

A mass of 4 kg is traveling over a quarter circular ramp with a radius of 10 meters. At the bottom of the incline the mass is moving at 21.3 m/s and at the top of the incline the mass is moving at 2.8 m/s. What is the work done by all non-conservative force in Joules?

Answers

Answer:

499.7 J

Explanation:

Since total mechanical energy is conserved,

U₁ + K₁ + W₁ = U₂ + K₂ + W₂ where U₁ = potential energy at bottom of incline = mgh₁, K₁ = kinetic energy at bottom of incline = 1/2mv₁² and W₁ = work done by friction at bottom of incline, and U₂ = potential energy at top of incline = mgh₂, K₁ = kinetic energy at top of incline = 1/2mv₂² and W₂ = work done by friction at top of incline. m = mass = 4 kg, h₁ = 0 m, v₁ = 21.3 m/s, W₁ = 0 J, h₂ = radius of circular ramp = 10 m, v₂ = 2.8 m/s, W₂ = unknown.

So, U₁ + K₁ + W₁ = U₂ + K₂ + W₂

mgh₁ + 1/2mv₁²  + W₁ = mgh₂ + 1/2mv₂²  + W₂

Substituting the values of the variables into the equation, we have

mgh₁ + 1/2mv₁²  + W₁ = mgh₂ + 1/2mv₂²  + W₂

4 kg × 9.8 m/s²(0) + 1/2 × 4 kg × (21.3 m/s)²  + 0 = 4 kg × 9.8 m/s² × 10 m + 1/2 × 4 kg × (2.8 m/s)²  + W₂

0 + 2 kg × 453.69 m²/s² = 392 kgm²/s² + 2 kg × 7.84 m²/s²  + W₂

907.38 kgm²/s² = 392 kgm²/s² + 15.68 kgm²/s²  + W₂

907.38 kgm²/s² = 407.68 kgm²/s² + W₂

W₂ = 907.38 kgm²/s² - 407.68 kgm²/s²

W₂ = 499.7 kgm²/s²

W₂ = 499.7 J

Since friction is a non-conservative force, the work done by all the non-conservative forces is thus W₂ = 499.7 J

You throw a glob of putty straight up toward the ceiling, which is 3.50 m above the point where the putty leaves your hand. The initial speed of the putty as it leaves your hand is 9.10 m/s.
1. What is the speed of the putty just before it strikes the ceiling? Express your answer with the appropriate units.
2. How much time from when it leaves your hand does it take the putty to reach the ceiling? Express your answer with the appropriate units.

Answers

Answer:

Explanation:

Given that:

the putty initial speed (u) = 9.10 m/s

distance (s) between hand and the ceiling = 3.50 m

the speed of the putty prior to the time it hits the ceiling can be determined by considering the second equation of motion.

v² - u² = 2as

Since the putty is moving in a vertical motion(i.e. in an upward direction)

v² - u² = -2gs

v² = u² - 2gs

[tex]v = \sqrt{u^2 - 2gs}[/tex]

[tex]v = \sqrt{(9.10)^2 -( 2* 9.8) (3.50 -0)}[/tex]

[tex]v = \sqrt{82.81 -19.6 (3.50)}[/tex]

[tex]v = \sqrt{82.81 -68.6}[/tex]

[tex]v = \sqrt{14.21}[/tex]

v = 3.77 m/s

2.

The time it takes to reach the ceiling from the moment it leaves your hand can be calculated by using the first equation of motion:

v = u + at

In an upward direction

v = u - gt

making time t the subject;

v - u = -gt

[tex]t = \dfrac{v-u}{-g}[/tex]

[tex]t = \dfrac{3.77 - 9.10}{-9.8}[/tex]

[tex]t = \dfrac{-5.33}{-9.8}[/tex]

t = 0.54s

quick answer please

.
.
.Five identical capacitor plates each of area A are arranged such that adjacent plates are at a distance d apart . The plates are connected to a potential difference of EMF V as shown in the figure. The capacitance :

Answers

Answer:

tq1=EoA/D

-2q1=-2EoAV/d

Option C.

Answer:

tq1=EoA/D

-2q1=-2EoAV/D

Explanation:

option C is correct

A motorist travels due North at 90 km/h for 2 hours. She changes direction and travels West at 60 km/for 1 hour.
a) Calculate the average speed of the motorist [4]
b) Calculate the average velocity of the motorist.

Answers

Answer:

a. 50km/hr.

b. 10km/hr

Explanation:

Average speed, which is calculated by dividing the total distance travelled by the time interval as follows:

Average speed = total distance travelled ÷ time

Average velocity is calculated by dividing the total displacement by the time interval as follows:

Average velocity = change in displacement (∆x) ÷ time (t)

According to this question, a motorist travels due North at 90 km/h for 2 hours. She then changes direction and travels West at 60 km/for 1 hour.

Total distance of this journey is 90 + 60 = 150

Total time taken = 1 + 2 = 3hours

Average speed = 150/3

= 50km/hr.

b.) Average velocity = x2 - x1/t

Average velocity = 90 - 60/3

= 30/3

= 10km/hr

Study the position-time graph for a bicycle. Which statement is supported by the graph? Position vs Time O The bicycle has speed but not velocity. O The bicycle is moving at a constant velocity. O The bicycle has a displacement of 3 m. O The bicycle is not in motion. 3 Position (m) 0 1 2 3 4 5 Time (s) Next Submit Save and Exit Mark this and return tViewers/AssessmentViewer/Activit. 0 M M​

Answers

Answer:

D) The bicycle is not in motion.

Explanation:

Study the position-time graph for a bicycle.

Which statement is supported by the graph?

A) The bicycle has speed but not velocity.

B) The bicycle is moving at a constant velocity.

C) The bicycle has a displacement of 3 m.

D) The bicycle is not in motion.

Solution:

Velocity is the time rate of change of displacement. It is the ratio of displacement to time taken.

Speed is the time rate of change of distance. It is the ratio of distance to time taken.

From the position-time graph, we can see that the bicycle has a constant positon of 3 m for the whole of the time. That is the position remains 3 m even as the time changes. Therefore, we can conclude that the bicycle is not in motion.

From the position-time data provided, it can concluded that the bicycle is not in motion.

Motion

Motion of a body involves a change in the position of that body with time.

A body in motion is constantly changing position or orientation as time passes.

The body may move with constant velocity/speed or changes in its velocity.

A position-time graph provides information about the motion of a body.

From the data provided:

At time 0, the bicycle is at position 3At time 1, the bicycle is at position 3At time 2, the bicycle is at position 3At time 3, the bicycle is at position 3At time 4, the bicycle is at position 3At time 5, the bicycle is at position 3

The position of the bicycle remains the same for all time intervals.

Therefore, from the position-time data provided, it can concluded that the bicycle is not in motion.

Learn more about motion and position-time graph at: https://brainly.com/question/2356782

An air-filled pipe is found to have successive harmonics at 700 Hz , 900 Hz , and 1100 Hz . It is unknown whether harmonics below 700 Hz and above 1100 Hz exist in the pipe. What is the length of the pipe

Answers

Answer:

the length of the pipe is 0.85 m or 85 cm

Explanation:

Given the data in the question;

The successive harmonics are;  700 Hz , 900 Hz , and 1100 H

Now, for a closed pipe,

length of pipe (L) = λ/4

Harmonics; 1x, 3x, 5x, 7x, 9x, 11x

1100Hz - 900Hz = 200Hz

⇒ 2x = 200Hz

x = 100Hz ( fundamental frequency )

λ = V/f = 340 /100 = 3.4 m

Now

Length L = λ / 4

L = 3.4 / 4

L = 0.85 m or 85 cm

Therefore, the length of the pipe is 0.85 m or 85 cm

A photon with a frequency of 5.02 × 1014 hertz is absorbed by an excited hydrogen atom. This causes the electron to be ejected from the atom, forming an ion. Calculate the energy of this photon in joules. [Show all work, including the equation and substitution with units.] Determine the energy of this photon in electron-volts. What is the number of the lowest energy level (closest to the ground state) of a hydrogen atom that contains an electron that would be ejected by the absorption of this photon?

Answers

Answer:

Explanation:

An atom emits a photon (particle of light) when transitioning from a ground state to its excited state. To obey conservation of energy, the energy gained by the atom when an electron moves to a lower energy level is equal to the energy it loses in emitting the photon. (The energy of a photon is E = hf, where E is the energy, h is Planck's constant, and f is the frequency of the photon.) Conversely, when an atom absorbs a photon (as is the case in absorption spectra), the electron absorbing the photon moves to a higher energy level.

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Which equation represents a line with a slope of 13 and a y-intercept of -1? In which point of view is the narrator a character in the story?first personomniscient third personlimited third person Name two traits that the most recent common ancestor of a whale and a human probably had. hey, another math question Math problem please help thank youuuuuu PLEASE HELP ME PLEASE!!! hii guys I'm sorry I am close to failin, and I sorry tay I'm asking a lot for questions :c In 2020, Amanda set up Coverdell education savings accounts for each of her four grandchildren, aged 7, 9, 14, and 16. She would like to contribute the annual maximum to each savings account when she usually makes other annual-election gifts every year on December 31. The annual maximum for 2020 is $2,000. How much can she contribute in total to the Coverdell education savings accounts in 2020 and each of the next four years Which of the following defines the term foreign policy?A. actions are taken to improve the well-being of people around the globeB. a monetary system in which prices worldwide are set by the ratio between the world's supply of gold and the world's level of economic activityC. the country's plan for dealing with other countries and peoples of the worldD. President Monroe declared that the United States would stay out of European conflicts and that European nations must stay out of North and South America Can someone help me out with these few problems 1,3,4,6,7,10,12,15Please only reply back if you really are trying to help me please no spam I would really appreciate it HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP I WILL GIVE BRAINLIEST 13. If you have (100 3 5x + 3) in your wallet, you got a gift of (10 3 + 3x) and you spent (80 3 2 2 +9) in buying food, how much money is left in your pocket? Create a program that calculates the cost of a meal and drink in a restaurant. Display a small menu with three meals, three drinks and the price for each. The program should have the following functions: my_restaurant(): This function displays the menu and asks the user to choose a meal and a drink. It also calls the my_meal() and my_beverage() functions. my_meal(): This function allows the user to choose a meal and return the choice. my_beverage(): This function allows the user to choose a drink, size small, medium or, large, and returns the choice. meal_cost(): This function receives a parameter that represents the meal choice. Calculate the cost of the meal based on the users choice. beverage_cost() This method receives two parameters that represents the drink and size. Calculate the cost of the beverage based on the users choice. total_cost() This function calculates the grand total for the meal and drink. Calculate the sales tax at 6%. drop and drag each characteristic into the correct category Everyone know that the chicken crossed the road, but not why. Can you figure out why the TURKEY crossed the road? . The wind ---------(blow)the leaves away.(Fill with past perfect tense please tell There are 1,453 souvenir paperweights that need to be packed in boxes. Each box will hold 17 paperweights. How many boxes will be needed? The times taken by 18 people to complete a puzzle are shown A plant costs p dollars and a bush costs b dollars. Ana buys 2 plants and 4 bushes for $42. Paola buys 7 plants and 9 bushes for $107. Write down a pair of simultaneous equations and solve them to find out the value of p and the value of b. In a wire, when elongation is 4 cm energy stored is E. if it is stretched by 4 cm, then what amount of elastic potential energy will be stored in it?