A 50,0 g silver spoon at 20.0°C is placed in a cup of coffee at
90.0°C. How much heat does the spoon absorb from the coffee to
reach a temperature of 89.0°C?

Answers

Answer 1

The heat capacity of the silver spoon at the given temperature difference is 817.65 J.

Heat capacity of the silver spoon

The heat capacity of theb silver spoon is the quantity of heat absorbed by the silver spoon. The heat capacity of the silver spoon at the given temperature difference is calculated as follows;

Q = mcΔθ

where;

m is mass of the spoonc is specific heat capacity of silver = 0.237 J/g⁰CΔθ is change in temperature

Q = 50 x 0.237 x (89 - 20)

Q = 817.65 J

Thus, the heat capacity of the silver spoon at the given temperature difference is 817.65 J.

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Related Questions

How does energy affecf a wave?

Answers

The energy transported by a wave is directly proportional to the square of the amplitude. So whatever change occurs in the amplitude, the square of that effect impacts the energy. This means that a doubling of the amplitude results in a quadrupling of the energy.

Two blocks each of mass m are attached to the ends of a massless rod

Answers

The net torque on this system is (ml2g-ml1g)k

What is Torque?

This refers to the type of force that causes rotation in objects which has mass and is a twisting force

Based on the complete question, we can see the given parameters:

The torque due to farther mass above the pivot is ml2gk

The torque due to nearer mass about the pivot is ml1gk

Therefore, the net torque is (ml2g-ml1g)k

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The net torque on this system in which two blocks each of mass m are attached to the ends of a massless rod, above pivot, is (ml₂g-ml_₁g)\hat k.

What is torque?

The torque of a body is the rate of change of angular momentum of the body. Torque is the product of moment of inertia and the angular acceleration.[tex]\tau =I\times \alpha[/tex][tex]\tau=mlg[/tex]

Here, (I) is the moment of inertia and (α) is the angular acceleration.

Two blocks each of the mass m are attached to the ends of a massless rod which pivots as shown in fig.

Initially, the rod is held in the horizontal position and then released. When, the mass was kept at farther to pivot, then the value of torque is,

[tex]\tau=ml_2g\hat k[/tex]

When, the mass was kept at nearer to pivot, then the value of torque is,

[tex]\tau=-ml_1g\hat k[/tex]

Thus, the net torque on this system above pivot is,

[tex]\tau=ml_2g\hat k+(-ml_2g\hat k)\\\tau=(ml_2g-ml_1g)\hat k[/tex]

Thus, the net torque on this system in which two blocks each of mass m are attached to the ends of a massless rod, above pivot is (ml₂g-ml_₁g)\hat k.

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A block of mass 3. 0 kg is hung from a spring, causing it to stretch 12 cm at equilibrium, as shown above. The 3. 0 kg block is then replaced by a 4. 0 kg block, and the new block is released from the position shown above, at which the spring is unstretched. How far will the 4. 0 kg block fall before its direction is reversed?.

Answers

Answer: 32 cm

Explanation:

If you wanted to melt ice, then heat it up, and get the water to just barely vaporize, how many equations would you need to solve for the energy used in this procedure?

Answers

Two equations will be needed to solve for the energy used in this procedure.

What is Energy?

This is defined as the ability or capacity to do work. Ice being converted to vapor requires energy and the equations are seen below:

H₂O₍s₎  ⇒ H₂O₍l₎

H₂O₍l₎ ⇒ H₂O₍g₎

These are the equations which are used to calculate energy with heat being involved in both reactions.

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How much energy does a pair of hair straighteners transfer every second

Answers

Answer:

It depends...

Explanation:

If you know how much watts the pair of hair straighteners use, you can use that as the energy every second. A normal flat iron for hair would be 300 watts, so we could say that it uses 300 jolts or watts of energy per second.

A 50 kg object moving at 15 m/s collides with another 50 kg object moving in the same direction at 10 m/s. If the collision is inelastic, what is the final velocity of the two objects after they combine?

Answers

Answer:

12.5 m/s

Explanation:

By conservation of momentum, we have that:
[tex]\displaystyle m_1v_1 + m_2v_2 = m_1v_1' + m_2v_2'[/tex]

Because the two objects combine after collision, they will have the same velocity:

[tex]\displaystyle m_1v_1 + m_2v_2 = (m_1+m_2)v_f[/tex]

Substitute and solve for final velocity:

[tex]\displaystyle \begin{aligned} (50 \text{ kg})(15\text{ m/s}) + (50\text{ kg})(10\text{ m/s}) & = ((50+50)\text{ kg})v_f \\ \\ v_f & = 12.5\text{ m/s}\end{aligned}[/tex]

In conclusion, the final velocity of the system will be 12.5 m/s.

If a number of coplanar forces acting on a particle are in equilibrium, then

Answers

Explanation:

Then the algebraic sum of the moment of all the forces about any point is equal to the moment of the resultant force about the same point

If a number of coplanar forces acting on a particle are in equilibrium. then the moment of their resultant is equal to the sum of their individual moment.

What is the law of moments?

If a number of co-planar forces operating on a particle are in equilibrium, the algebraic sum of their moments about any point equals the moment of their resultant force about the same point, according to the law of moments.

Hence If a number of coplanar forces acting on a particle are in equilibrium. then the moment of their resultant is equal to the sum of their individual moment.

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Thunder is heard 7.2 seconds after a bolt of lightning is observed. if the speed of sound is 349 m/s, how far away did the lightning strike?

Answers

Answer:

2512.8 meters

Explanation:

s=d/t

by using speed formula

Seismic waves do not travel along the Earth’s surface. Please select the best answer from the choices provided T F.

Answers

Seismic waves do not travel along the Earth’s surface. The statement is false.

what are seismic waves?

The seismic waves can be defined as the waves full of energy that travel through the Earth's layer, these waves are the result of earthquake.

They can further be divided into two types body wave and surface waves. The body waves travel in the interior of the Earth and the surface waves travel at the surface of the Earth.

The seismic waves can have an amplitude of few centimeters in large earthquake. They travel slower as compared to the body waves.

Hence Seismic waves do not travel along the Earth’s surface. The statement is false.

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Answer:

False

Explanation:

Ed 2022

A proton is moving south with a speed of 4500 m/s in a magnetic field of 5500 T directed into the page. Determine the magnitude and direction of the magnetic force on the charge.

a.3.96 x 10-12 N west
b.1.55 x 1026 west
c.1.55 x 1026 east
d.3.96 x 10-12 N east

Answers

Answer:

F = q V X B

V is south and B is into the page

The resultant vector is directed to the East

F = 1.6E-19 * 4.5E3 * 5.5E3 N = 3.96 N East

(Note q is negative for an electron producing a force in the opposite direction)

If a train going 60 m/s hits the brakes, and it takes the train 85 seconds to stop, what is
the train's acceleration?

Answers

Question :-

If a Train going with 60 m/s Speed hits the Brakes, and takes 85 sec to stop. What is the Acceleration of the Train ?

Answer :-

Acceleration of Train is 0.70 m/s² .

Explanation :-

As per the provided information in the given question, we have been given that the Speed of the Train is 60 m/s . Time taken to stop the Train is 85 sec . And, we have been asked to calculate the Acceleration of the Train .

For calculating the Acceleration , we will use the Formula :-

[tex] \bigstar \: \: \: \boxed { \sf{ \: Acceleration \: = \: \dfrac{v \: - \: u}{t} \: }} \\ [/tex]

Where ,

V denotes to Final Velocity .U denotes to Initial Velocity .T denotes to Time Taken .

Therefore , by Substituting the given values in the above Formula :-

[tex] \dag \: \: \: \: \sf{Acceleration \: = \: \dfrac{Final \: Velocity \: - \: Initial \: Velocity}{Time} } \\ [/tex]

[tex] \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{0 \: - \: 60}{85} } \\ [/tex]

[tex] \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{60}{85} } \\ [/tex]

[tex] \longmapsto \: \: \: \textbf {\textsf {Acceleration \: = \: 0.70 }} [/tex]

Hence :-

Acceleration = 0.70 m/s² .

[tex] \underline {\rule {210pt} {4pt}} [/tex]

Note :-

Kindly Scroll the Screen from Right to Left for Better View .

Answer:

Question :-

If a Train going with 60 m/s Speed hits the Brakes, and takes 85 sec to stop. What is the Acceleration of the Train ?

Answer :-

Acceleration of Train is 0.70 m/s² .

Explanation :-

As per the provided information in the given question, we have been given that the Speed of the Train is 60 m/s . Time taken to stop the Train is 85 sec . And, we have been asked to calculate the Acceleration of the Train .

For calculating the Acceleration , we will use the Formula :-

\begin{gathered} \bigstar \: \: \: \boxed { \sf{ \: Acceleration \: = \: \dfrac{v \: - \: u}{t} \: }} \\ \end{gathered}

Acceleration=

t

v−u

Where ,

V denotes to Final Velocity .

U denotes to Initial Velocity .

T denotes to Time Taken .

Therefore , by Substituting the given values in the above Formula :-

\begin{gathered} \dag \: \: \: \: \sf{Acceleration \: = \: \dfrac{Final \: Velocity \: - \: Initial \: Velocity}{Time} } \\ \end{gathered}

†Acceleration=

Time

FinalVelocity−InitialVelocity

\begin{gathered} \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{0 \: - \: 60}{85} } \\ \end{gathered}

⟼Acceleration=

85

0−60

\begin{gathered} \longmapsto \: \: \: \sf{Acceleration \: = \: \dfrac{60}{85} } \\ \end{gathered}

⟼Acceleration=

85

60

\longmapsto \: \: \: \textbf {\textsf {Acceleration \: = \: 0.70 }}⟼Acceleration = 0.70

Hence :-

Acceleration = 0.70 m/s² .

\underline {\rule {210pt} {4pt}}

Note :-

Kindly Scroll the Screen from Right to Left for Better View .

What is the electric potential energy of a charge that experiences a force of 3. 6 × 10–4 N when it is 9. 8 × 10–5 m from the source of the electric field? 3. 5 × 10–8 J 4. 6 × 10–4 J 2. 7 × 10–1 J 3. 7 × 100 J.

Answers

The electric potential energy of the charge will be =3.5*10^8 J  

What is Electric potential energy?

Electric potential energy is the energy that is needed to move a charge against an electric field.

F=Force experienced by the charge = 3.6*10^-4 N

q1 = magnitude of charge producing the electric field

q2 = magnitude of charge experiencing the electric force

r1 = distance between the two charges

Electric force experienced by the charge is given using coulomb's law as

[tex]F=\dfrac{kq_1q_2}{r^2}[/tex]

[tex]3.6\times 10^{-4}=\dfrac{9\times 10^9 q_1q_2}{(9.8\times 10^{-5})^2}[/tex]

[tex]q_1q_2=3.84\times 10^{-22}[/tex]

Electric potential energy of the charge can be given as

[tex]U=\dfrac{kq_1q_2}{r}[/tex]

[tex]U=\dfrac{(9\times 10^9)q_1q_2}{(9.8\times 10^{-5})^2}[/tex]

[tex]U=3.5\times 10^{-8}\ J[/tex]

Thus Electric potential energy of the charge can be given as [tex]U=3.5\times 10^{-8}\ J[/tex]

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A round tube weighs 30 lbs. If the tube is stood on end it pushes down on the floor with a pressure of
2 lbs/in?. How many square inches is the end of the tube?

Answers

Answer:

15in2

Explanation:

The diagram shows part of a radio antenna.The plastic tube protects the radio antenna from bad weather.Dust particles carried by the wind rub against the plastic tube.After some time, the dust particles cause the tube to become positively charged.State the property of plastic that allows it to become electrostatically charged.

Have a good day!! :>

Based on the first law of thermodynamics, the energy gained by a system is _____ the energy lost by the surroundings.

Answers

Based on the first law of thermodynamics, the energy gained by a system is equal to the energy lost by the surroundings.

Laws of thermodynamics

The laws of thermodynamics can be summarised as follow

The first law states that energy can neither be created nor destroyed. The second law states that the entropy of the universe will always increase for every spontaneous process. The third law states that for a perfect crystal at zero Kelvin, the entropy is zero.

From the laws given above precisely the first law, we can conclude that the energy gained by a system is equal to the energy lost by the surroundings

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Which scientist received a nobel prize for the discovery of x-rays?.

Answers

Answer:

That's Rontgen

Explanation:

Wilhem Rontgen

A coffee filter of mass 1.3 grams dropped from a height of 3 m reaches the ground with a speed of 0.5 m/s. How much kinetic energy Kair did the air molecules gain from the falling coffee filter

Answers

Answer: .0380575J

Explanation:

The coffee filter originally only had potential energy, which can be found by:

PE = m * g * h → PE = .0013 * 9.8 * 3 = .03822 J

*Note the mass must be in kg!!!

All of this energy should be converted to kinetic energy, but the air molecules take some of the energy; the energy they gain can be found by finding how much energy the filter has at the bottom of its fall, and subtracting this from the original energy to see how much was lost;

All of the energy at the bottom equals kinetic energy, which can be found by:

KE = 1/2 * m * v^2 → KE = 1/2 * .0013 * .5^2 = .0001625 J

Thus, the air gained .03822 - .0001625 = .0380575J :)

The particles that make up matter are ______, ions or molecules.

Answers

Answer:

Atoms.

Explanation:

Atoms are purely one bit of an element. Ions are positive or negative atoms. Molecules are not pure, they have other stuff with it.

Which terrestrial planet exhibits retrograde rotation?.

Answers

Answer:

Planets that are farther from the sun than the earth (all but Mercury and Venus) will exhibit retrograde motion.

If the position of the planet is observed relative to the background stars, the planet will appear to move backward relative to the stars when the earth is moving in an Eastward direction faster than the planet, and the planet appears to move backwards relative to the stars

(The planet will be on the side of the earth that is opposite that of the sun)

Knowing the direction of heat flow, explain why if you leave a hot bowl of soup out in the open on the countertop, it eventually gets cold. Where is the heat going?

Answers

The heat will flow towards the air surrounding the soup bowl and towards the countertop below the bowl.

Where does the heat go?

We know that when two bodies of different temperatures there will be a flow of heat between the objects, from the hotter one to the colder one.

In this case, we have the bowl of soup as the hot object, and the ambient (the countertop, the air surrounding the bowl, etc) itself will be the cooler object.

Then the heat will flow towards the air surrounding the soup bowl and towards the countertop below the bowl.

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What is the tension of the string if the cylinder has an acceleration of

Answers

In physics, the tension on a suspended object said to be equal to the weight of the object plus or minus the mass of the object times the acceleration acting on it.

~ ISS

Which statement describes the force diagram? the forces are balanced. the box will move to the right. the box will move to the left. the forces are unbalanced.

Answers

The answer will be A The forces are balanced. Force is an external agent applied on any object to displace it from its position. Force is a vector quantity, so with magnitude it also requires direction.

what is force?

Force is an external agent applied on any object to displace it from its position. Force is a vector quantity, so with magnitude it also requires direction. Direction is necessary to examine the effect of the force and to find the equilibrium of the force.

The length of each arrow represents the magnitude of each force, while the direction of each arrow represents the direction of each force.

From the diagram, we see that the four arrows have all same length: this means that the four forces have same magnitude, therefore they are balanced in pair. In fact:

On the vertical direction, the normal reaction ([tex]F_N[/tex]) balances the weight of the box ([tex]F_g[/tex])

On the horizontal direction, the push ([tex]F_P[/tex]) balances the force of friction ([tex]F_f[/tex])

Hence the answer will be A. the forces are balanced.

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Answer:

A is your answer.

Explanation:

Good luck on your exam!

Control rods are used to slow down the reaction in the reactor core when the core becomes too hot. please select the best answer from the choices provided t f

Answers

In nuclear reactors, control rods are used because reactions that occur in a nuclear reactor are highly exothermic in nature.

What is a nuclear reactor?

A nuclear reactor is an apparatus or structure in which  radioactive material can be made to undergo a commanded, self-sufficient nuclear reaction with the resultant release of energy.

Therefore, when these control rods are infused in a nuclear reactor, than it absorbs the neutrons and helps to control the chain reaction. As a result, the rate of chain reaction gets in control.

Thus, we can conclude that the statement control rods are used to slow down the reaction in the reactor core when the core becomes too hot is a true statement.

Thus In nuclear reactors, control rods are used because reactions that occur in a nuclear reactor are highly exothermic in nature.

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Answer:

TRUE ( T )

Explanation:

Just took the test on edge

Two equivalent sinusoidal waves travel toward each other on a spring they interfere. What if the waves traveling toward each other aren't sinusoidal but a series of pulses as seen in the picture? What effect does this have on the spring?

Answers

Answer:

Superposition would take place

Explanation:

The waves would interfere with one another either in the form of Constructive Interference or Destructive Interference.

4. Point B on a wheel of radius 40 cm that is rotating at a constant 5. 0 revolutions

per second is located 0. 20 m from the axis of rotation. Pont A is just at the border

of the wheel. See the figure.

a) What is the angular velocity of the wheel in rad/s?

b) What point has a greater linear speed, A or B? Calculate both speeds and

compare the results.

c) What are the centripetal accelerations of points A and B due to the spin of the

wheel? Sketch the situation and represent the vectors linear velocity and

centripetal acceleration in points A and B. Assume the rotation of the wheel

to be clockwise.

Answers

Answer:

SD

Explanation:

When a 10-V battery is connected to a resistor, 2 A of current flow in the resistor. What is the resistor's value

Answers

Hi there!

We can use Ohm's law to solve:
[tex]V = IR[/tex]

V = Potential Difference (V)
I = Current (A)
R = Resistance (Ω)

We can rearrange the equation to solve for resistance:

[tex]R = \frac{V}{I}[/tex]

Plug in the given values to solve.  

[tex]R = \frac{10}{2} = \boxed{5 \Omega}[/tex]

dont use me for points please i need help, (circuits for physics)

Answers

Answer:

B, A, A, B

Explanation:

Just trust me on this one.

Students in science are studying solutions and the dissolving rate of solids. One group was given some instant lemonade mix to dissolve. They used a packet of lemonade crystals and a packet of lemonade powder. The students dissolved the same amount of each solid into 100 ml of water. They varied the water temperature. List ALL the possible conclusions based the data the students collected?

Answers

Answer:

a-d

Explanation:

hope this helps

Imagine a situation : If people could not see colours, then how would traffic lights work ? Design a traffic system that does not rely on colors.​

Answers

Answer:

position

Explanation:

Okay, so this already exists

Colorblind people use the position of the light

Red on top, yellow in middle, green on bottom

The amount of potential energy possessed by an elevated object is:.

Answers

...equal to the work done in lifting it.


Which choice most accurately traces the flow of electrons in the circuit?

this is wrong
Electrons move counterclockwise from side B of the battery to side A of the battery through each lightbulb.​

Answers

Electron flow out of the negative terminal, through the circuit and into the positive terminal of the source is accurate about Electron flow.

What is electron flow?

Electron flow is the current produced by the movement of free electrons moving along a positive terminal; the direction of electron flow is opposite to that of current.

Electron flow out of the negative terminal, through the circuit and into the positive terminal of the source.

Therefore, Electron flow out of the negative terminal, through the circuit and into the positive terminal of the source is accurate about Electron flow.

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