In the popular game "Angry Birds" (refer Figure), for the red bird to hit the green bird with their range 55.0 m, what should be the launch angle (with respect to the horizontal) of the slingshot if the time of flight is 2.50 s? ​

In The Popular Game "Angry Birds" (refer Figure), For The Red Bird To Hit The Green Bird With Their Range

Answers

Answer 1

Answer:

Explanation:

What are we to use as gravity in this imaginary world? I will ASSUME 9.81 m/s² and assume no air resistance.

horizontal velocity component

vx = 55.0/2.50 = 22 m/s

vertical initial velocity component

(12.0 - 10.0) = 0 + vy₀(2.50) + ½(-9.81)2.50²

vy₀ = 13.0625 m/s

θ = arctan(vy₀/vx) = arctan(13.0625/22) = 30.6997225... = 30.7°


Related Questions

Given the force diagram of the basketball, what can you tell about the basketball motion?

Answers

Newton's laws allow to find the result for the movement of the basketballl:

On the vertical axis the ball is on the ground. On the horizontal axis the ball is accelerating in the direction of the pushing force.

Newton's laws establish the relationship between the forces on objects:

The 1st law states that if the net force is zero the object is stationary or with constant speed. The 2nd law gives a relation of the force with the mass and the acceleration of the body. The 3rd. Law states that the force appears in pairs, one on each body with the same magnitude, but in the opposite direction.

Let's apply these principles to the ball's motion diagram.

The two vertical forces are in the opposite direction, one is due to the weight of the body and the other is the attraction of the earth to the support of the ball, they are of equal magnitude, not their action-reaction force and reluctant because it is applied to the same body

       In conclusion we can say that the ball is on the ground.

The two horizontal forces are in the opposite direction, the thrust force is greater than the friction therefore using Newton's second law the ball must be accelerating in the direction of the thrust force.

       In conclusion we can say that the ball is accelerating in the direction of the pushing force.

In conclusion using Newton's laws we can find the result for the motion of the basketball:

On the vertical axis the ball is on the ground. On the horizontal axis the ball is accelerating in the direction of the pushing force.

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Consider 5.00 mol of liquid water. (a) What volume is occupied by this amount of water? The molar mass of water is 18.0 g/mol. (b) Imagine the molecules to be, on average, uniformly spaced, with each molecule at the center of a sma11 cube. What is the length of an edge of each sma11 cube if adjacent cubes touch but don't overlap? (c) How does this distance compare with the diameter of a molecule?

Answers

This question involves the concepts of density, volume, and mass.

(a) The volume occupied by this amount of water is "90 m³".

(b) The length of an edge of each small cube is "83 μm".

(c) The length of the edge of each small cube is "equal" to the diameter of a molecule.

(a)

The volume can be found using the following formula:

[tex]V = \frac{nM}{\rho}[/tex]

where,

V = volume occoupied = ?

n = no. of moles = 5 mol

M = molar mass = 18 g/mol

[tex]\rho[/tex] = density of water = 1 g/m³

Therefore,

[tex]V=\frac{(5\ mol)(18\ g/mol)}{1\ g/m^3}\\\\[/tex]

V = 90 m³

(b)

First, we will find the volume of an individual molecule:

[tex]V_i =\frac{V}{nN_A}[/tex]

where,

[tex]N_A[/tex] = Avogadro's number = 6.02 x 10²³ molecules/mol

Therefore,

[tex]V_i=\frac{90\ m^3}{5\ mol(6.02\ x\ 10^{23}\ molecules/mol)}[/tex]

Vi = 3 x 10⁻²³ m³

This volume can be given as a volume of the sphere:

[tex]V_i=\frac{4}{3}\pi r^3\\\\r=\sqrt[3]{\frac{3(3\ x\ 10^{-23}\ m^3)}{4\pi}}[/tex]

r = 4.15 x 10⁻⁷ m

Diameter = d = 2r = 2(4.15 x 10⁻⁷ m)

d = 8.3 x 10⁻⁷ m = 83 μm

since the cubes are adjacent to each other. Therefore, the diameter will be equal to the edge length.

Edge Length = L = d

L = 8.3 x 10⁻⁷ m = 83 μm

(c)

The edge length is equal to the diameter of the molecule.

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You are traveling along a freeway at 65 mi/h. You suddenly skid to a stop because of congestion in traffic. Where is the energy that your car once had as kinetic energy before you stopped

Answers

The work and energy theorem allows finding the result for where the kinetic energy of the car is before stopping is:

    The energy becomes:

An important part in work on discs. A part in non-conservative work due to friction.

Work is defined by the scalar product of force and displacement.

          W = F . d

Where the bold indicate vectors, W is work, F is force and d is displacement.

The work energy theorem relates work and kinetic energy.

            W = ΔK = [tex]K_f - K_o[/tex]

In this case the vehicle stops therefore its final kinetic energy is zero, consequently the work is:  

          W = - K₀

Therefore, the initial kinetic energy that the car has is converted into work in its brakes.  In reality, if assuming that there is friction, an important part is transformed into non-conservative work of the friction force, this work can be seen in a significant increase in the temperature of the discs on which the work is carried out.

In conclusion, using the work-energy theorem we can find the result for where the kinetic energy of the car is before stopping is:

    The energy becomes:

An important part in work on the discs. A part in non-conservative work due to friction.

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An object with mass 1.2 kg is moving at a constant speed in a circle with radius 2.5 m. If the
object makes exactly 12 revolutions in a 1 minute, what is the acceleration of the object?

Answers

Answer:

3.9m/s² is the acceleration

The acceleration of the object is 3.9m/s².

How do you find the acceleration of an object?

Acceleration (a) is the change in velocity (Δv) over the change in time (Δt), represented by the equation a = Δv/Δt. This allows you to measure how fast velocity changes in meters per second squared (m/s^2).

What is an example of an object that has acceleration?

When you fall off a bridge. The car turning at the corner is an example of acceleration because the direction is changing. The quicker the turns, the greater the acceleration.

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Pls help me with this one :)) ​

Answers

Answer:

Row A is correct

Explanation:

both conduction and convection require mass to complete any heat transfer. A vacuum contains no mass

Which of the following best describes an achievement test that is given at the end of a learning segment to evaluate mastery of objectives?

Answers

Answer

An Achievement test is an assessment of developed knowledge or skill. ... Achievement tests are developed to measure skills and knowledge learned in a given grade level, usually through planned instruction, such as training or classroom instruction. Achievement tests are often contrasted with aptitude tests.

Explanation:

2. If a vehicle with four wheels is traveling in a linear path through soft dirt, how many and which tires would you expect to leave tire track impressions

Answers

Given our understanding of the situation, for this vehicle with four wheels is traveling in a linear path through soft dirt, we would expect for only two wheels to leave tire track impressions.

The vehicle has four wheels, and one might think initially that it makes sense for all four wheels to create tire track impressions on the dirt. This assessment is correct, all four tires will create impressions, However, not all four tires will leave a said impression.

This is due to the fact that as the vehicle advances, the tires in the back will erase the impressions left by the front tires. Therefore, only two tire track impressions will be left.

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Two identical vertical springs S1 and S2 have masses m1 = 400 g and m2 = 800 g attached to them. If m1 causes spring S1 to stretch by 4 cm, what is the ratio of the potential energy of S1 and S2? Use g = 10 m/s^2

Select one:

a. 1:2

b. 4:1

c. 1:4

d. 1:3

e. 2:1​

Answers

Answer:

potential energy = mgh

= 400÷1000 × 10× 4÷100

= 0.4 × 10 × 0.04

=4/10 ×10×4/100

= 4/10 × 4/10

=16/100

= 0.16 joules

m1 (400) stretches 4cm

m1 (100g) stretches 1cm

so, m2(800g) stretches 8 cm

potential energy of m2 = mgh

= 800/1000 ×10×8/100

= 0.8 × 0.8

=8/10 ×8/10

= 64/100

=0.64 joules

Ratio of s1 to s2

16/100 ÷ 64/100

= 1:4 ( answer)

Pls help, I really need it and plz show steps I will give brainliest..

Answers

Answer:

21.31 meters

Explanation:

Since we're working with gravitational potential energy (GPE):

GPE (Joules) = mass (kg) * gravity (m/s^2) * height (meters)

1. Figure out what we have:

GPE = mass * gravity * height

We're looking for height, and we have the other three, so we're set to move on.

2. Isolate the unknown variable (height):

(GPE) / (mass * gravity) = height

3. Plug in your numbers:

(3.78 * 10^7 J) / ((1.81 * 10^5 kg) * (9.8 m/s^2)) = 21.31 meters

please answer fast in hindi ​

Answers

Answer:

1. Dheere Dheere (slowly slowly)

2. Har (every)

3. Kal (tomorrow)

4. Mat (don't)

5. Andar (inside)

sorry I wasn't able to write in hindi

convert -40⁰ c to Fahrenheit scale​

Answers

Answer:

104f

Explanation:

(40°C × 9/5) + 32 = 104°F

104 Fahrenheit had this question in math class

What is the momentum of a 3 kg bowling ball moving at 3 m/s?
.
O 1 kg. m/s
O 3 kg. m/s
O 6 kg. m/s
O 9 kg • m/s

Answers

Explanation:

p = mv

p denotes momentumm denotes massv denotes velocity

→ p = 3 kg × 3 m/s

p = 9 kg.m/s

Option D is correct.

What are the three factors discussed in our live session that can lead to success through challenging physical activities:

Talent, flexibility, and stamina


Strength, balance, and endurance


Knowledge, attitude, and fitness level


Attitude, motivation, and determination

Answers

Answer:

Attitude, motivation and determination

Explanation:

Let me know if I'm right.

The factors leading to the success through the challenging physical activities are Attitude, motivation and determination.

Although the information regarding the live session is not mentioned, but as a general point of view, the major factors that need to considered while undergoing through the challenging physical activities are as follows:

Attitude - Attitude is one of the major factor leading to the management of challenges. A positive attitude always creates a base to face the initials of physical activities.Motivation - Motivation is another aspect that needs to be considered while undergoing the physical activities. Motivation comes from some sort of positive words from a specific person, thereby reducing the changes of poor start.Determination - The half battle is conquered with self-determination, a highly determined person is always has an add-on advantage for the task that he/she is going to start.

Thus, we can conclude that the factors leading to the success through the challenging physical activities are Attitude, motivation and determination.

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An astronaut is doing thee simple pendulum experiment on a different planet to measure the acceleration due to gravity. If the length of the pendulum is 45 cm and the period of oscillations is equal to 1.428 s, what is the acceleration due to the gravity of the planet

Answers

The acceleration due to gravity on the given planet is 8.71 m/s².

The given parameters;

Length of the pendulum, L = 45 cm Period of the oscillation, T = 1.428 s

The acceleration due to gravity on the planet is calculated by applying following formula as follows;

[tex]T = 2\pi \sqrt{\frac{l}{g} } \\\\\frac{T}{2 \pi } = \sqrt{\frac{l}{g}} \\\\\frac{T^2}{4\pi ^2} = \frac{l}{g} \\\\g = \frac{4\pi^2 l}{T^2} \\\\g = \frac{4 \times (\pi)^2 \times 0.45}{1.428^2} \\\\g = 8.71 \ m/s^2[/tex]

Thus, the acceleration due to gravity on the given planet is 8.71 m/s².

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Heat is transferred from molecules with more kinetic energy to molecules with _________kinetic energy.

Answers

Answer:

low

Explanation:

the higher the kinetic energy, the More the vibration of molecules, thus heat is more on the side with highly vibrating molecules

1. It’s fall and time for the corn maze and bonfire and you just can’t wait. On your way to the farm though a turkey flies out in front of you, so you slam on the brakes and go from from 30.0 m/s to 18.0 m/s. Luckily your date brought a stop watch and told you the whole thing took place in 10.5s. What is your acceleration and how far did you go?

Answers

Acceleration = (change in velocity ( final speed - starting speed))/ (time)

Acceleration = (18-30)/10.5

Acceleration = -12/10.5

Acceleration = -1.14 m/s^2

Distance = 30m/s x 10.5s + 1/2(1.14)(10.5)^2

Distance = 252.2 meters

I was in Anchorage Alaska during the Summer Solstice. The sun rose around 3am and set around 1 am the next day-- almost 24 hours of sunlight. If the tilt of the Earth was changed to be 10 degrees, how would the length of daylight in Alaska change at the Summer Solstice

Answers

Answer:

Daylight hours would be shorter.

Explanation:

If there were no tilt of the axis at all, every place on the planet except the north and south poles would have 12 hours of daylight and 12 hours of night every day of the year.

At a 10° tilt, the arctic circle and antarctic circles would be a little less than half the distance from the poles as they are today.

Why should people pay attention to scientists when making decisions?
A. Scientists are always correct.
B. Sclentists are the smartest people.
C. Scientists make the best decisions.
D. Scientists back up their statements with facts.

Answers

Answer:

D. Scientist back up their statements with facts.

Explanation:

The majority of the laws, theorems and thesis are base on with experiments. The follow different strategies for confirm the hypothesis with facts, one of the most famous models is the scientific method. That is a way of proof something in a trustworthy.

In the image is the resume about this method (graphical organizer).

A camera takes a properly exposed photo at f/5.6 and 1/250 s. What shutter speed should be used if the lens is changed to f/4.0?

a.1/65 s
b.1/125 s
c.1/250 s
d.1/500 s
e.1/1000 s

Answers

The shutter speed that should be used if the lens is changed to f/4.0 is; Choice D: 1/500 s.

The relationship between the shutter speed and the focal ratio is an inverse relationship.

Ratio of Areas = 5.6²/4²

A1/A2 = 1.96 = 2

Since; T1A1 = T2A2

T2 = T1(A1/A2)

T2 = 250 × 2 = 500 seconds

In essence; when the focal ratio is reduced as in this case; from f/5.6 to f/4.0; the shutter speed is increased.

Ultimately, the shutter speed of the camera in discuss increases to; 1/500 s.

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Light bulbs produce useful energy in the form of light and waste energy in the form of heat. What kind of light bulb would you use
to incubate eggs?

A. low-efficiency light bulbs, because they produce more light

B. low-efficiency light bulbs, because they produce more heat

C. high-efficiency light bulbs, because they produce more heat

D. high-efficiency light bulbs, because they produce more light

Answers

Answer:

C) high efficiency light bulbs, because they produce more heat

Light bulbs produce useful energy in the form of light and waste energy in the form of heat, the kind of light bulb would you use to incubate eggs are low-efficiency light bulbs, because they produce more heat, therefore the correct answer is option B.

What is thermal energy?

It can be defined as the form of the energy in which heat is transferred from one body to another body due to their molecular movements, thermal energy is also known as heat energy.

The type of light bulb you would use to incubate eggs is a low-efficiency light bulb since they produce more heat; consequently, option B is the right response. Light bulbs produce useful energy in the form of light and waste energy in the form of heat.

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If a baseball has a mass of 0.075kg and is traveling with an acceleration of 25 m/s^2. What is the force that the baseball will hit the bat?

Thanks in Advance!

Answers

The force of the baseball is 1.86 N

The first step is to write out the parameters given in the question;

mass of the ball is 0.075 kg

acceleration of the ball is 25 m/s²

Force is what makes objects move, force can change the initial shape of an object, it can also change the speed at which it move. Force can be calculated by multiplying mass and acceleration of the object.

Force= mass × acceleration

0.075 × 25

= 1.86 N

Hence the force of the baseball is 1.86 N

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trình bày những hiểu biết cơ bản về năng lượng

Answers

Answer:

I don't understand your language

What is the angle θ between vectors A⃗ and B⃗ if A⃗ =4ı^−4ȷ^ and B⃗ =−5ı^+7ȷ^?

Answers

The characteristics of the scalar product allows to find the angle between the two vectors is:

The angle θ = 170º

The scalar product is the product between two vectors whose result is a scalar.

            A . B = |A|  |B| cos θ

Where A and B are the vectors, |A| and |B| are the modules of the vectors and θ at the angle between them.

The vector is given in Cartesian coordinates and the unit vectors in these coordinates are perpendicular.

            i.i = j.j = 1

            i.j = 0

            A . B = (4 i - 4j). * -5 i + 7j)

            A . B = - 4 5 - 4 7

            A. B = -48

We look for the modulus of each vector.

           |A| = [tex]\sqrt{x^2 +y^2 }[/tex]

           |A| = [tex]\sqrt{4^2 + 4^2}[/tex]  

           |A| = 4 √2

          |B| = [tex]\sqrt{5^2 +7^2}[/tex]

          |B| = 8.60

We substitute.

            -48 = 4√2  8.60  cos θ

            -48 = 48.66 cos θ

            θ = cos⁻¹   [tex]\frac{-48}{48.664}[/tex]  

            θ = 170º

In conclusion using the dot product we can find the angle between the two vectors is:

the angle θ = 170º

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Ryder is testing the change in motion for an object that weighs 25 kg and an object that weighs 30 kg. He will push each object with the same force. Ryder predicts the object that weighs 25 kg will have a greater change in motion. Is this correct?

Yes, the object with the smaller mass will have a greater change in motion.
No, the change in motion for both objects will be the same.
Yes, the mass is greater, and the object will have a greater change of motion.
No, neither of the objects will have a change in motion.

Answers

Ryder is testing the change in motion for an object that weighs 25 kg and an object that weighs 30 kg. Then, the greater change in motion is due to the greater mass of the object, and the object will have a greater change of motion. Thus, the correct option is C.


What is Motion?

Motion is the phenomenon in which an object changes its position with respect to the time taken. Motion of an object is mathematically described in terms of the displacement covered by the object, the distance, velocity, acceleration, speed and the frame of reference to an observer and measurement of the change in the position of the body of an object relative to that particular frame with the change in time taken.

The motion of an object is proportional to the mass of the object. The mass is greater in this case, and therefore the objects will have a greater change of motion.

Therefore, the correct option is C.

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How much heat must be removed from 1.61 kg of water at 0 ∘C to make ice cubes at 0 ∘C?

Answers

Answer:

Explanation:

All

A cylindrical rod formed from silicon is 16.8 cm long and has a mass of 2.17 kg. The density of silicon is 2.33 g/cm3 . What is the diameter of the cylinder

Answers

Answer:

We are given the length, the mass and the density of the cylinder. First let us calculate for the volume by dividing the mass by the density.

volume = mass /density

where mass = 2.17 kg = 2170 g, therefore:

volume = 2170 g / (2.33 g/cm^3)

volume = 931.33 cm^3

 

We know that the volume of a cylinder has the formula:

volume = π r^2 h

since h = 16.8 cm, therefore calculating for radius:

931.33 cm^3 = π r^2 (16.8 cm)

r^2 = 17.646 cm^2

r = 4.2 cm

 

Hence the diameter (d) is:

d = 2 r

d = 8.4 cm

Explanation:

The diameter of the cylindrical rod is approximately 0.382 cm.

To find the diameter of the cylindrical rod, we can use the formula for the volume of a cylinder and then solve for the diameter.

The formula for the volume of a cylinder is:

V = π[tex]r^{2}[/tex]h,

where V is the volume, r is the radius, and h is the height (or length) of the cylinder.

In this case, we know the length of the cylinder (h) is 16.8 cm. We need to find the radius (r) in order to calculate the diameter.

The mass of the cylinder can be related to its volume and density using the formula:

m = ρV,

where m is the mass, ρ is the density, and V is the volume.

Rearranging this formula, we can solve for V:

V = m / ρ.

Now we have two equations:

V = π[tex]r^{2}[/tex]h,

V = m / ρ.

Setting these two equations equal to each other, we can solve for r:

π[tex]r^{2}[/tex]h = m / ρ.

Substituting the given values:

π[tex]r^{2}[/tex] * 16.8 cm = 2.17 kg / (2.33 g/[tex]cm^3[/tex]).

Let's solve this equation for r:

[tex]r^{2}[/tex] = (2.17 kg / (2.33 g/[tex]cm^3[/tex])) / (π * 16.8 cm).

[tex]r^{2}[/tex]  ≈ 0.036775 [tex]cm^2[/tex].

Taking the square root of both sides:

r ≈ 0.191 cm.

Finally, we can find the diameter (d) by multiplying the radius by 2:

d ≈ 2 * 0.191 cm.

d ≈ 0.382 cm.

Therefore, the diameter of the cylindrical rod is approximately 0.382 cm.

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In a model generator, a 310-turn rectangular coil 0.075 m by 0.18 m rotates with an angular frequency of 12.2 rad/s in a uniform magnetic field of 0.64 T. What is the maximum emf induced in the coil

Answers

This question involves the concepts of the induced emf, magnetic field, and angular frequency.

The maximum emf induced in the coil is "32.68 volts".

The following formula can be used to find out the induced emf in the coil.

[tex]E =N\omega AB\ Sin(\omega t)[/tex]

But, for maximum induced emf sin function should have a value of 1. Therefore,

[tex]E = N\omega AB[/tex]

where,

E = induced emf = ?

N = No. of turns in the coil = 310 turns

ω = angular frequency = 12.2 rad/s

A = Area of coil = (0.075 m)(0.18 m) = 0.0135 m²

B = magnetic field = 0.64 T

Therefore,

[tex]E=(310)(12.2\ rad/s)(0.0135\ m^2)(0.64\ T)[/tex]

E = 32.68 volts

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Alicia is naturally rather shy and is graduating from college. She will need to find a job, so she is starting to go on job websites and work on her
resume. She knows she should network, but it sounds a little intimidating. What is the BEST advice for Alicia?
ОА. If she is not comfortable networking, she will never find a job.
ОВ. The majority of jobs are found through networking, so she should really try it.
OC. Networking is overrated, so she can skip that part of the job search process.
OD If she is naturally shy, she probably has really poor social skills and should work on that.

Answers

Answer:

OB and i have no reasoning

A Vector that starts from
Origin is called what?

Answers

A vector that starts from origin is called a position vector

the wheel of bicycle has a radius of 25cm. what will be the magnitudes of the angular displacement in radian and revolution respectively, when the wheel has rolled a distance of 350cm on straight level road?​

Answers

Answer:

Explanation:

350 cm / 25 cm = 14 radians

14 rad / 2π rad/rev = 2.23 revolutions

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