1. When you talk into your paper cup telephone, the person on the other end can feel the bottom
of their telephone vibrate. Why do you think this happens?

Answers

Answer 1

Answer:

The correct answer is - the sound waves make vibration that travels through the string.

Explanation:

When an individual person talks into your paper cup telephone the person on the other end can feel the bottom of their cup vibrate. The sound waves create vibration go through the string that travels through the string to the end of the cup where vibrations can feel.

The sound waves are longitudinal waves that move or travel through different mediums like air, solid, or gas. The waves create vibration in the particles.

You could create a paper cup telephone but instead of using string, test out different materials and see if those materials will allow sound vibrations to travel through them


Related Questions

A massive truck of 1200N moving with a velocity of 2m/s hits a stationary mass of 30N. if the both bodies move together after the collision, determine their common velocity.​

Answers

Answer:

The common speed is 1.95 m/s

Explanation:

Law Of Conservation Of Linear Momentum

It states that the total momentum of a system of bodies is conserved unless an external force is applied to it. The formula for the momentum of a body with mass m and velocity v is  

P=mv.  

If we have a system of bodies, then the total momentum is the sum of all of them:

[tex]P=m_1v_1+m_2v_2+...+m_nv_n[/tex]

If a collision occurs, the velocities change to v' and the final momentum is:

[tex]P'=m_1v'_1+m_2v'_2+...+m_nv'_n[/tex]

In a system of two masses, the law of conservation of linear momentum

is written as:

[tex]m_1v_1+m_2v_2=m_1v'_1+m_2v'_2[/tex]

If both masses stick together after the collision at a common speed v', then:

[tex]m_1v_1+m_2v_2=(m_1+m_2)v'[/tex]

The common velocity after this situation is:

[tex]\displaystyle v'=\frac{m_1v_1+m_2v_2}{m_1+m_2}[/tex]

The truck of m1=1200 N (weight) travels at v1=2 m/s and hits a stationary mass (v2=0) of m2=30 N (weight). After the bodies collide, they keep moving together. Before we can calculate the common speed, we need to calculate the masses of the bodies, since they are given as weights.

[tex]m_1=\frac{P_1}{g}=\frac{1200}{9.8}=122.45 Kg[/tex]

[tex]m_2=\frac{P_2}{g}=\frac{30}{9.8}=3.06 Kg[/tex]

Now calculate the common speed:

[tex]\displaystyle v'=\frac{122.45 * 2+3.06 * 0}{122.45+3.06}[/tex]

[tex]\displaystyle v'=\frac{244.9}{125.51}=1.95\ m/s[/tex]

The common speed is 1.95 m/s

PLEASE HELP!!!!! which statements correctly conpare the masses of protons,neutrons,and electrons​

Answers

Protons and neutrons have similar mass
Electrons are smaller then a proton or a neutron

a car and its passengers have a mass of 1200kg it is travelling at 12m/s.
Calculate the increase in kinetic energy when the car increases its speed to 18 m/s.

Show clearly how you work out your answer and give the unit.

Answers

Answer:

The increase of kinetic energy is 108,000 J

Explanation:

Kinetic Energy

Is the energy an object has due to its state of motion. It's proportional to the square of the speed and the mass.

The equation for the kinetic energy is:

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

Where:

m = mass of the object

v = speed at which the object moves

The kinetic energy is expressed in Joules (J)

A car has a total mass of m=1,200 kg and travels at v1=12 m/s. Then it increases its speed at v2=18 m/s.

It's required to compute the increase of kinetic energy. We'll calculate both energies K1 and K2 and then subtract them.

[tex]\displaystyle K_1=\frac{1}{2}1,200*12^2=86,400\ J[/tex]

[tex]\displaystyle K_2=\frac{1}{2}1,200*18^2=194,400\ J[/tex]

The increase of kinetic energy is:

[tex]\Delta K=K_2-K_1 =194,400\ J-86,400\ J[/tex]

[tex]\Delta K=108,000\ J[/tex]

The increase of kinetic energy is 108,000 J

The shape of Sugarloaf mountain, in Rio de Janeiro, Brazil, is such that, if you
were to kick a soccer ball hard enough, it could land near the base of the mountain
without hitting the mountain's side. Suppose the ball is kicked horizontally with an
initial speed of 9:37 m/s. If the ball travels a horizontal distance of 85.0 m, how tall
is the mountain?

Answers

Answer:

The mountain is 403 m tall

Explanation:

Horizontal Launch

When an object is thrown horizontally with a speed v from a height h, it describes a curved path ruled by gravity until it hits the ground.

The range or maximum horizontal distance traveled by the object can be calculated as follows:

[tex]\displaystyle d=v\cdot\sqrt{\frac {2h}{g}}[/tex]

It's given that if a ball is kicked from the top of the Sugarloaf Mountain, it will land near its base without hitting the side. The initial speed is v=9.37 m/s and it reaches a horizontal distance of d=85 m. Solving the equation for h:

[tex]\displaystyle h=\frac{d^2g}{2v^2}[/tex]

Substituting:

[tex]\displaystyle h=\frac{85^2*9.8}{2*9.37^2}[/tex]

[tex]\displaystyle h=403 \ m[/tex]

The mountain is 403 m tall

What is the change in momentum of a ball if a force of 5.0 N acts on it for a brief time of 4 ms?

Answers

Answer:

0.02 Ns

Explanation:

From the question given above, the following data were obtained:

Force (F) = 5 N

Time (t) = 4 ms

Change in momentum =?

Next, we shall convert 4 ms to s. This can be obtained as follow:

1 ms = 1×10¯³ s

Therefore,

4 ms = 4 ms × 1×10¯³ s / 1 ms

4 ms = 4×10¯³ s

Thus, 4 ms is equivalent to 4×10¯³ s

Change in momentum = Impulse

Impulse (I) = Force (F) × time (t)

Change in momentum = Force (F) × time (t)

Force (F) = 5 N

Time (t) = 4×10¯³ s

Change in momentum =?

Change in momentum = 5 × 4×10¯³

Change in momentum = 0.02 Ns

Therefore, the change in the momentum of the ball is 0.02 Ns.

which topic are you most likely to find in a physics textbook?

Answers

I think D would be the best answer provided.

A lizard accelerates from 12.0 m/s to 40.0 m/s in 6 seconds. What is the lizard’s average acceleration?

Answers

Answer:

[tex]\boxed {\boxed {\sf \frac{14}{3} \ or \ 4.6667 \ m/s^2}}[/tex]

Explanation:

Acceleration can be found using the following formula.

[tex]a=\frac{v_f-v_1}{t}[/tex]

where [tex]v_f[/tex] is the final velocity, [tex]v_i[/tex] is the initial velocity and t is the time.

The lizard started at 12.0 m/s and accelerated up to its final velocity of 40.0 m/s in 6 seconds.

Therefore:

[tex]v_f= 40.0 \ m/s \\v_i= 12.0 \ m/s \\t= 6 \ s[/tex]

Substitute the variables into the formula.

[tex]a=\frac{40.0 \ m/s - 12.0 \ m/s}{6 \ s}[/tex]

Solve the numerator first and subtract.

40.0 m/s - 12.0 m/s= 28 m/s

[tex]a=\frac{ 28 \ m/s}{6 \ s}[/tex]

Divide.

[tex]a= \frac{14}{3} \ m/s/s= \frac{14}{3} \ m/s^2[/tex]

[tex]a=4.66667 \ m/s^2[/tex]

The lizard's average acceleration is 14/3 or 4.66667 m/s²

Answer:

4 2/3 m/s

Explanation:

first thing to find the average acceleration is to figure out what the increase in speed was, we can do that by subtracting the original speed from the speed after accelerating, that looks like:

40 - 12 = 28

so the lizard accelerated 28 m/s in 6 seconds, to find the average increase in m/s every second, we divide the m/s by the seconds, which gives us:

28 / 6 = 4.66 = 4 2/3 m/s

According to the workshop, habits, attitudes, feelings and thoughts
contribute to 60% of your college success.
contribute to 30% of your college success.
contribute to 70% of your college success.
contribute to 100% of your college success.

Answers

Answer:

60%

Explanation:

A batter hits a fastball with a mass of 0.145 kg that was traveling at 40.0 m/s; the force exerted by the bat on the ball is 29 N. What is the time of contact with the ball in order to reverse its motion at its original speed?

Answers

The force applies an acceleration in the reverse direction of

29 N = (0.145 kg) a   →   a = 200 m/s²

and in order to hit the ball back with speed 40.0 m/s, this acceleration is applied over time t such that

200 m/s² = (40.0 m/s - (-40.0 m/s)) / t   →   t = (80.0 m/s) / (200 m/s²) = 0.4 s

A 1.47-newton baseball is dropped from a height of 10.0 meters and falls through the air to the ground. The kinetic energy of the ball is 12.0 joules the instant before the ball strikes the ground. What is the maximum amount of mechanical energy converted to internal energy during the fall?

Answers

Answer:

See the explanation below.

Explanation:

First, we must determine the mass of the baseball, we know that the weight of a body is defined as the product of mass by gravity.

[tex]w=m*g[/tex]

where:

w = weight = 1.47[N]

m = mass [kg]

g = gravity acceleration = 9.81 [m/s²]

Now replacing:

[tex]m=w/g\\m = 1.47/9.81\\m = 0.149[kg][/tex]

We now know that kinetic energy is converted to potential energy as the ball descends. By means of the following equation, we can determine the potential energy when the baseball is 10 meters high.

[tex]E_{pot}=m*g*h\\[/tex]

where:

Epot = potential energy [J]

m = mass = 0.149[kg]

g = gravity acceleration = 9.81 [m/s²]

h = elevation = 10 [m]

Now replacing:

[tex]E_{pot}=0.149*9.81*10\\E_{pot}=14.7[J][/tex]

In theory, this same energy must be converted to kinetic energy just before the ball hits the floor. But we see that we only have 12 [J] of kinetic energy.

That is to say, that of the 14 [J] that were had as potential energy (mechanical energy) 2 [J] was converted to internal energy, and the rest was converted to kinetic energy (mechanical energy)

[tex]E_{int}=14-12\\E_{int}=2[J][/tex]

Note: Potential, kinetic and elastic energies are forms of mechanical energy.

A brick of gold is 0.1 m wide, 0.1 m high, and 0.2 m long. The density of gold is 19,300 kg/m3. What pressure does the brick exert on the table if the brick is resting on its side?

Answers

Answer:

The pressure exerted by the brick on the table is 18,933.3 N/m².

Explanation:

Given;

height of the brick, h = 0.1 m

density of the brick, ρ = 19,300 kg/m³

acceleration due to gravity, g = 9.81 m/s²

The pressure exerted by the brick on the table is calculated as;

P = ρgh

P = (19,300)(9.81)(0.1)

P = 18,933.3 N/m²

Therefore, the pressure exerted by the brick on the table is 18,933.3 N/m².

Suppose someone caused a book to fall from the shelf to the ground. Compared to the total sum of kinetic and potential energy the book has while on the shelf, about how much would it have when it is halfway from the shelf to the ground? no energy, half as much,twice as much, or the same amount? Pretty easy question.​

Answers

Answer:

book resting on a shelf has no potential energy relative to the shelf since it has a height of zero meters relative to the shelf. However, if the book is elevated to some height above the shelf, then it has potential energy proportional to the height at which it resides above the shelf.

An object can have both kinetic and potential energy at the same time. For example, an object which is falling, but has not yet reached the ground has kinetic energy because it is moving downwards, and potential energy because it is able to move downwards even further than it already has. The sum of an object's potential and kinetic energies is called the object's mechanical energy.

As an object falls its potential energy decreases, while its kinetic energy increases. The decrease in potential energy is exactly equal to the increase in kinetic energy.

Another important concept is work.

Grizzly bears are known to run really fast. What is the momentum of a grizzly bear (about 420 pounds) running at 17 m/s ?
How fast should a 250 lb human run to match the momentum of the grizzly bear ?

Answers

Answer:

A. Momentum of the grizzly bear is 3241.56 Kgm/s

B. The human will run at 28.56 m/s

Explanation:

A. Determination of the momentum of the grizzly bear.

Mass of grizzly bear = 420 lb

Velocity of grizzly bear = 17 m/s

momentum of the grizzly bear =?

Next, we shall convert 420 lb to Kg. This can be obtained as follow:

1 lb = 0.454 kg

Therefore,

420 lb = 420 lb × 0.454 Kg / 1 lb

420 lb = 190.68 Kg

Thus, 420 lb is equivalent to 190.68 Kg

Finally, we shall determine the momentum of the grizzly bear as follow:

Mass of grizzly bear = 190.68 Kg

Velocity of grizzly bear = 17 m/s

momentum of the grizzly bear =?

Momentum = mass × velocity

Momentum = 190.68 × 17

Momentum = 3241.56 Kgm/s

Thus, the momentum of the grizzly bear is 3241.56 Kgm/s

B. Determination of how fast the human will run.

Mass of human = 250 lb

Momentum of human = momentum of the grizzly bear

Momentum of the grizzly bear is 3241.56 Kgm/s

Momentum of human = 3241.56 Kgm/s

Velocity of human =?

Next, we shall convert 250 lb to Kg. This can be obtained as follow:

1 lb = 0.454 kg

Therefore,

250 lb = 250 lb × 0.454 Kg / 1 lb

250 lb = 113.5 Kg

Thus, 250 lb is equivalent to 113.5 Kg

Finally, we shall determine how fast the human will run as follow:

Mass of human = 113.5 Kg

Momentum of human = 3241.56 Kgm/s

Velocity of human =?

Momentum = mass × velocity

3241.56 = 113.5 × velocity

Divide both side by 113.5

Velocity = 3241.56 / 113.5

Velocity = 28.56 m/s

Therefore, the human will run at 28.56 m/s to match the momentum of the grizzly bear

which of the following is an application of of the technology developed by Charles kuen kao
A. Producing shock-resistant cameras
B. Predicting earthquakes
C. Transmitting digital information
D. Developing safer spaceships

Answers

D because it’s most wanted and I see the people through it and I know because I love it
the answer would be D

The world’s largest wind turbine has blades that are 80 m long and makes 1 revolution every 5.7 seconds. What is the velocity for one of the blades? (THIS IS physics, CIRCULAR MOTION)?

Answers

Answer:

The free end of the blade has a tangential velocity of about 88.19 m/s

Explanation:

The angular velocity of the blades is  [tex]2 \pi /5.7\,\,rad/sec[/tex]

since the blades are 80 m long, then the tangential velocity of the free end of the blade is:

[tex]v_{tan} \approx 88.19\,\,m/s[/tex]

1. A race car moves along a circular track of radius 100m at a velocity of 25m/s. (a) What is
the time taken to complete one lap of the circular track. (b) What is the time taken for 10
laps.

Answers

Given :

A race car moves along a circular track of radius 100m at a velocity of 25m/s.

To Find :

(a) What is  the time taken to complete one lap of the circular track.

(b) What is the time taken for 10  laps.

Solution :

Circumference of circular track,

[tex]C = 2\pi r\\\\C = 2\times \pi \times 100\ m\\\\C = 628.32 \ m[/tex]

a) Time taken to complete one lap is :

[tex]t= \dfrac{628.32}{25}\ s\\\\t =25.13 \ s[/tex]

b) Time taken to complete 10 laps is :

[tex]t_{10} = 10\times t\\\\t_{10} = 10\times 25.13\ s\\\\t_{10} = 251.3\ s[/tex]

Hence, this is the required solution.

please help!!! Will give u Brainliest

Answers

The correct answer is c because the other three is incorrect.

Please click on the ❤️. Thanks!

Create an energy path in the Gizmo, starting at the Sun. For each step of the path, describe the energy conversion that takes place. The first one is done for you. Discuss your answers with your classmates and teacher.

Answers

Explanation:

Sun— Nuclear energy is converted to heat and light energy

Corn absorbs sunlight in order to produce sugars and oxygen for plant growth.

Corn is fermented to produce ethanol, which is burned to power generators to give an electrical current The speaker takes the electrical current and produces sound.

Answer:

sun, corn, corn, speaker

Explanation:

i took the k-12 test! have an amazing day! XX <3

The sun is located in the center of the system model because the sun: __________. *
1. is the least massive object in the system, and more massive objects orbit less massive objects.

2.is the most massive object in the system, and less massive objects orbit more massive objects

3. has the lowest temperature, and hotter objects orbit cooler objects.

4. has the highest temperature, and cooler objects orbit hotter objects.

Answers

Answer:

2.is the most massive object in the system, and less massive objects orbit more massive objects

is considered as a single focus by the objects describing elliptical paths about the sun.

1. Which one of the following physical quantities is formed after dividing
mass by volume?​

Answers

Answer:

xxxxx

Explanation:

Density is the mass of an object divided by its volume. Density often has units of grams per cubic centimeter (g/cm3). Remember, grams is a mass and cubic centimeters is a Volume (the same volume as 1 milliliter).

what is formulae method​

Answers

Answer:

Explanation:

The formula method is used to calculate termination payments on a prematurely ended swap, where the terminating party compensates the losses borne by the non-terminating party due to the early termination.

A baseball pitcher delivers a pitch by exerting an average force of 15 N for a time interval of 0.42 s. How much impulse does he impart to the ball ?

Answers

Answer:

6.3Ns

Explanation:

Impulse can be calculated by using the formula as follows:

I = F × ∆t

Where;

I = impulse (Ns)

F = Force exerted (N)

∆t = change in time (s)

According to the information provided in the question, I = ?, F = 15N, ∆t (time interval) = 0.42s

I = 15 × 0.42

I = 6.3Ns

what are the two conditions for work done​

Answers

2 conditioner are

Explanation:

force applied and displacement produced

URGENT
A force of 35 N is used to stretch a spring 15 cm beyond its normal length. What is the
increase in the spring's energy?

Answers

Answer:

5.25 J

Explanation:

W = PE = (f)(x)

PE = 35N*0.15m

PE = 5.25 N*m

1 N*m = 1 J

PE = 5.25 J

A boy on a swing set has a speed of 4.5 m/s and a centripetal acceleration of 8.1 m/s2 at the bottom of his swing. How long are the ropes of the swing?

Pls help!!!!

Answers

Answer:

R = 1.8 m

Explanation:

This is a simple harmonic movement exercise, at the bottom of the swing the acceleration is vertical upwards and the speed is tangential to the trajectory, that is horizontal; the expression for the centralized acceleration is

              [tex]a_{c}[/tex] = v² / R

              R = v² /a_{c}

where the radius is equal to the length of the swing

let's calculate

            R = 8.1 / 4.5

            R = 1.8 m

a body is under going non uniform circular motion work done by tangential force on body is​

Answers

Answer:

The tangential force will act as a torque on the body, increasing its angular velocity and thus also increasing its kinetic energy. By the work-kinetic-energy theorem, work has been done on the body. Yes, in non-uniform circular motion the work done on the object is non-zero, for the reason you stated.

Explanation:

HELP PLEASE
Balloons and static electricity
Answer the following questions:

Answers

Can’t see the pictures !

Two bolls with a masses m and 2m are connected by a rod of negligible mass. The rod can be rotated in several positions along the rod. To obtain the greatest angular accretion for a fix torque applied Determine the position of the torque applied to obtaim the greatest angular acceleration 2m.

Answers

Answer:

\alpha  = \frac{2F}{3m} \ \frac{1}{r}

maximmun x =r

Explanation:

In this exercise we are asked for the maximum angular acceleration, let's start by writing the second law of / newton for rotational motion. Let's fix our reference system at the midpoint of the bar that has a length 2r

       Σ τ  = (I₁ + I₂) α

where I₁ and I₂ moment of inertia of the capsule with masses m and 2m, respectively. Let's treat these capsules as point particles

       I₁ = m r²

       I₂ = 2m r²

the troque of a pair of force is the force times the distance perpendicular to the point of application of the force which is the same for both forces, we will assume that the counterclockwise rotation is positive

      Στ  = F x + F x

the angular acceleration is the same because they are joined by the bar of negligible mass, let us substitute

     2 F x = (m r² + 2m r²) α

     α = [tex]\frac{2F x}{3m r^{2} }[/tex]

     α = [tex]\frac{2F }{3m } \ \frac{x}{r^{2} }[/tex]

let's analyze this expression

* for the application point in the center (x = 0) at acceleration is zero

* for the point of application of the torque at the ends the acceleration is

              [tex]\alpha = \frac{2F}{3m} \ \frac{1}{r}[/tex]

this being its maximum value

8. What are the two types of mechanical waves?
Otransverse, electromagnetic
O longitudinal, infrared
Otransverse, longitudinal

Answers

The answer would be “Transverse, Longitudinal”

Determine the absolute pressure on the bottom of a swimming pool 30.0 mm by 8.5 mm whose uniform depth is 2.0 mm .

Answers

Answer:

To calculate the absolute pressure we used the depth as 2 m instead of 2 mm because the given dimensions for the swimming pool do not make sense (they are too small).  

The absolute pressure on the bottom of a swimming pool is 1.21x10⁵ Pa.

Explanation:

The absolute pressure is given by:

[tex]P_{A} = P_{g} + P_{atm}[/tex]

Where:

[tex]P_{g}[/tex]: is the gauge pressure

[tex]P_{atm}[/tex]: is the atmospheric pressure = 1 atm = 101325 Pa

The gauge pressure can be found as follows:

[tex]P_{g} = \rho gh[/tex]

Where:

ρ: is the density of water = 1000 kg/m³

g: is the gravity = 9.81 m/s²

h: is the height or the depth

Since the given dimensions in the statement for the swimming pool do not make sense (they should be in meters instead of millimeters), we will use h = 2 m.

[tex]P_{g} = \rho gh = 1000 kg/m^{3}*9.81 m/s^{2}*2.0 m = 19620 Pa[/tex]

Hence, the absolute pressure is:

[tex]P_{A} = P_{g} + P_{atm} = 19620 Pa + 101325 Pa = 120945 Pa = 1.21 \cdot 10^{5} Pa[/tex]        

Therefore, the absolute pressure on the bottom of a swimming pool is 1.21x10⁵ Pa.

I hope it helps you!                                                  

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