Ask question

Ask question

All categories

1 year ago

8

A 15.0-gram lead ball at 25.0°C was heated with 40.5 joules of heat. Given the specific heat of lead is 0.128 J/g∙°C, what is th

e final temperature of the lead?

1 answer:

mr Goodwill [35]1 year ago

3 0

Answer:

$T=4985.5^{\circ}K$

Explanation:

The equation that relates heat Q with the temperature change $T-T_0$ of a substance of mass <em>m </em>and specific heat <em>c </em>is $Q=mc(T-T_0)$ .

We want to calculate the final temperature <em>T, </em>so we have:

$T=\frac{Q}{mc}+T_0$

Which for our values means (in this case we do not need to convert the mass to Kg since <em>c</em> is given in g also and they cancel out, but we add $273^{\circ}$ to our temperature in $^{\circ}C$ to have it in $^{\circ}K$ as it must be):

$T=\frac{Q}{mc}+T_0=\frac{40.5J}{(15g)(0.128J/g^{\circ}C)}+(298^{\circ}K)=4985.5^{\circ}K$

You might be interested in

Fermi energy of conduction electrons in silver is 0.548 J. Calculate the number of such electrons in unit cm3

ICE Princess25 [194]

Answer:

$n=1.86*10^{-30}m^3$

Explanation:

From the question we are told that:

Fermi energy of conduction electrons $E_f=0.548J$

Generally the equation for Fermi energy is mathematically given by

$E_f=\frac{3}{\pi}^2/3*\frac{h^2}{8m}*{n^{2/3}}$

$E_f=\frac{3}{\pi}^2/3*\frac{h^2}{8m}*{n^{2/3}}$

${n^{2/3}}=\frac{E_f}{\frac{3}{\pi}^2/3*\frac{h^2}{8m}}$

Where

h= Planck's constant

${n^{2/3}}=\frac{E_f}{\frac{3}{\pi}^2/3*\frac{h^2}{8m}}$

${n^{2/3}}=\frac{0.548J}{3.62*10^{-19}}$

$n=(1.51*10^{-20})^{3/2}$

$n=1.86*10^{-30}m^3$

3 0

1 year ago

YALL PLEASE HELP QUICK!!!!!!!11!!!1!!1

Sever21 [200]

The purpose of the experiment is to describe how the plasma membrane contributes to how the cell functions.

<h3>How to explain the experiment?</h3>

The dependent variable is the variable bring investigated. In this case, the dependent variable is the egg circumference.

The independent variable is the variable controlled by the researcher.

The controlled variable has no influence on the results. An example is the concentration of vinegar.

A hypothesis is a proposition which can be tested by observations. In order to form a hypothesis, it's important to collect observations about the problem being examined.

The tools that can be used to collect data include observations and records taken.

The procedure to collect the data include:

Determine the information be collected.
Set a timeline for the collection of data.
Determine the method to utilize for data collection.
Analyze the data.
Implement the findings.

The conclusions that can be drawn about how the sum of forces acting on an object affect its motion is that when the forces cancel out, then the resultant force will be zero, if not, the unbalanced force will result in the acceleration of the object.

Learn more about experiments on:

brainly.com/question/17274244

#SPJ1

4 0

9 months ago

1, Condensation occurs when:

andrey2020 [161]

Answer:

1. surface water changes to vapor water

2. runs off into streams and rivers

3. transpiration

Explanation:

1. the water above the surface is being heated by the sun turning into a gas that makes up part of the cloud.

2. a runoff is the process of precipitation running down hills and into rivers and streams

3. Transpiration is essentially evaporation of water from plant leaves.

4 0

2 years ago

Read 2 more answers

Please help me! It states constant speed but moving in circular motion. I know there is acceleration due to a rate of change of

Morgarella [4.7K]

Direction of resultant force in circular motion is directed towards the center of the circle. Hence vector B is the direction of the resultant force.

8 0

2 years ago

A spherical shell is rolling without slipping at constant speed on a level floor. What percentage of the shell's total kinetic e

IgorC [24]

Answer:

41.667 per cent of the total kinetic energy is translational kinetic energy.

Explanation:

As the spherical shell is rolling without slipping at constant speed, the system can be considered as conservative due to the absence of non-conservative forces (i.e. drag, friction) and energy equation can be expressed only by the Principle of Energy Conservation, whose total energy is equal to the sum of rotational and translational kinetic energies. That is to say:

$E = K_{t} + K_{r}$

Where:

$E$ - Total energy, measured in joules.

$K_{r}$ - Rotational kinetic energy, measured in joules.

$K_{t}$ - Translational kinetic energy, measured in joules.

The spherical shell can be considered as a rigid body, since there is no information of any deformation due to the motion. Then, rotational and translational components of kinetic energy are described by the following equations:

Rotational kinetic energy

$K_{r} = \frac{1}{2}\cdot I_{g}\cdot \omega^{2}$

Translational kinetic energy

$K_{t} = \frac{1}{2}\cdot m \cdot R^{2}\cdot \omega^{2}$

Where:

$I_{g}$ - Moment of inertia of the spherical shell with respect to its center of mass, measured in $kg\cdot m^{2}$ .

$\omega$ - Angular speed of the spherical shell, measured in radians per second.

$R$ - Radius of the spherical shell, measured in meters.

After replacing each component and simplifying algebraically, the total energy of the spherical shell is equal to:

$E = \frac{1}{2}\cdot (I_{g} + m\cdot R^{2})\cdot \omega^{2}$

In addition, the moment of inertia of a spherical shell is equal to:

$I_{g} = \frac{2}{3}\cdot m\cdot R^{2}$

Then, total energy is reduced to this expression:

$E = \frac{5}{6}\cdot m \cdot R^{2}\cdot \omega^{2}$

The fraction of the total kinetic energy that is translational in percentage is given by the following expression:

$\%K_{t} = \frac{K_{t}}{E}\times 100\,\%$

$\%K_{t} = \frac{\frac{1}{2}\cdot m \cdot R^{2}\cdot \omega^{2} }{\frac{5}{6}\cdot m \cdot R^{2}\cdot \omega^{2} } \times 100\,\%$

$\%K_{t} = \frac{5}{12}\times 100\,\%$

$\%K_{t} = 41.667\,\%$

41.667 per cent of the total kinetic energy is translational kinetic energy.

7 0

2 years ago