HELP!!!
7. A block rests on a frictionless table on Earth. After a 20-N horizontal force is applied to the
block, it accelerates at 3.9 m/s^2.Then the block and table are carried to the moon, where the
acceleration due to gravity is 1.62 m/s^2. A horizontal force of 10 N is then applied to the block.
What is the acceleration?
A)2.0 m/s2
B)2.1 m/s2
C)1.8 m/s2
D)2.3 m/s2
E)2.5 m/s2

Answer:

1) T ≈ 50.318°C

2) It is due to the variation of the molar heat capacity of solid copper with temperature

3) The entropy introduced in the one mole of copper at 0°C is 4.146 J/K

The entropy introduced in the second mole of copper at 100°C is -3.548 J/K.

Explanation:

1) The given parameters are;

The temperature of 1 mole of copper = 0°C

The temperature of the second mole of copper 100°C

The specific heat capacity of copper = 22.64 + 6.28 × 10⁻³·T J/(mole·K)

The heat gained by the copper at 0° = The heat lost by the one mole of copper at 100°C

The total heat gained and lost is given as follows;

[tex]\int\limits^{T_f}_{273} {c_p} \, dT= -\int\limits^{T_f}_{373} {c_p} \, dT[/tex]

[tex]\int\limits^{T_f}_{273} {22.64 + 6.28 \times 10^{-3}\cdot T} \, dT= -\int\limits^{T_f}_{373} {22.64 + 6.28 \times 10^{-3}\cdot T} \, dT[/tex]

22.64·([tex]T_f[/tex] - 273) +  (6.28 × 10⁻³)/2×([tex]T^2_f[/tex] - 273²) = - 22.64·([tex]T_f[/tex] - 373) -  (6.28 × 10⁻³)/2×([tex]T^2_f[/tex]  - 373²)

Which gives;

0.00314 × [tex]T^2_f[/tex] + 22.64 × [tex]T_f[/tex] - 6414.74 = -0.00314 × [tex]T^2_f[/tex] - 22.64 × [tex]T_f[/tex] + 8881.59

Transferring the right hand side of the equation to the left and collecting the like terms gives approximately;

0.00628× [tex]T^2_f[/tex] + 45.28 × [tex]T_f[/tex] - 15296.33 = 0

Factoring with a graphing calculator, gives;

(T + 7533.509)·(T - 323.318)×0.00628 = 0

∴ T = 323.318 K ≈ 50.318°C

2) The common uniform temperature is not exactly 50°C because the hotter second mole of copper had a higher specific heat capacity, which resulted in the temperature at equilibrium being slightly higher than the average temperature

3) The amount of thermal energy transferred is given as follows;

22.64·(323.318 - 273) +  (6.28 × 10⁻³)/2×(323.318² - 273²) ≈ 1233.42 J

4) For the mole at 0°C, we have;

[tex]\Delta S_1 = \dfrac{\Delta Q}{T} =\int\limits^{323.318}_{273} { \left (\dfrac{22.64}{T} + 6.28 \times 10^{-3} \right)} \, dT\\\\\\\Delta S_1 = 22.64 \times ln \left ( \dfrac{323.318}{273} \right ) + 6.28 \times 10^{-3} \times (323.218 - 273) = 4.146 \ J/K[/tex]

The entropy introduced in the one mole of copper at 0°C, ΔS₁ = 4.146 J/K

For the mole at 100°C, we have;

[tex]\Delta S_2 = \dfrac{\Delta Q}{T} =\int\limits^{323.318}_{373} { \left (\dfrac{22.64}{T} + 6.28 \times 10^{-3} \right)} \, dT\\\\\\\Delta S_2 = 22.64 \times ln \left ( \dfrac{323.318}{373} \right ) + 6.28 \times 10^{-3} \times (323.218 - 373) = -3.548 \ J/K[/tex]

The entropy introduced in the second mole of copper at 100°C, ΔS₂ = -3.548 J/K.

Answer:

5 bulldogs

Explanation:

you need 4 bulldogs to beat 40 dragons, but since you would still need 3 dragons defeated, you would need another bulldog

Answer:

100km/h

Explanation:

500km/5 = 100km per hour

Answer:

Because the chemical energy is converted to electrical enegy in the cell phone

Explanation:

This set up is not a voilation of the first law of thermodynamics because the chemical energy is not lost, it is only being transformed into electrical energy.

According to the first law of thermodynamics "energy is neither created nor destroyed but transformed from one form to another".

It does not violate the first law of thermodynamics as the energy is being converted from one form to another.

As we use our phones, the amount of chemical energy in the battery decreases.  But it is not a violation of the first law of thermodynamics.

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Answer:

I. The angle θ increases, and the pattern expands away from the bright center

II. The angle θ increases, and the pattern expands away from the bright center

Explanation:

The given information are;

The light used to produce a diffraction pattern = Blue light

The formula for refraction is given as follows;

d × sin(θ) = n·λ

Where;

d = The inter slit distance

θ = The angle to the maxima

n = Number to the integer next fringe

λ = Light wavelength

The wavelength of blue light is between 450 and 495 nanometers

Therefore;

I. When we switch to yellow light

The wavelength of yellow light is between 590 and 560 nanometers, which is an increase in wavelength, given that d, the inter slit distance is held constant, the angle θ increases, and the pattern expands away from the bright center

II. Decrease the slit width

When the slit width is decreased, and the wavelength remains the same, the angle θ increases, and the pattern expands away from the bright center.

Given parameters:

Distance of Pigeon Forge = 58.25miles

Speed  = 62.5mile/hr

Unknown:

Time it will take Billy to get to Pigeon Forge = ?

Solution:

Speed is a physical quantity and it is the rate of change of distance with time.

       Speed  = [tex]\frac{distance}{time}[/tex]

     Now let us input the parameters and find the time;

               62.5  = [tex]\frac{58.25}{t}[/tex]

              58.25  = 62.5t

                   t = [tex]\frac{58.25}{62.5}[/tex]   = 0.93hrs

Time taken for him to get there is 0.93hrs

Answer:

The approximate acceleration of the sled is 0.319 m/s²

Explanation:

Given;

mass of the sled, m = 90 kg

horizontal applied force, f = 258 N

angle of inclination of the force, θ = 15°

coefficient of kinetic friction of 0.250, μ = 0.25

The net vertical force on the sled is given by;

Fcosθ - μmg = ma

258Cos15 - (0.25 x 90 x 9.8) = ma

249.2 - 220.5 = ma

28.7 = ma

a = 28.7 /m

a = 28.7 / 90

a = 0.319 m/s²

Therefore, the approximate acceleration of the sled is 0.319 m/s²

Answer:

The answer is C. 129.83 grams

Answer:

15mph

Explanation:

Because you've already done distance and time. Speed=distance divided by time. so it would be 300 divided by 20 giving you 15.

Answer:

The stone thrown upward lands farther away from the building.

Explanation:

Given that,

Angle = 30° above the horizontal

Speed = 18.0 m/s

Angle = 30° below the horizontal

Suppose, Which stone lands farther away from the building ?

We need to find which stone lands farther away from the building

Using formula of range

[tex]R=v_{x}t[/tex]

The horizontal velocity for the both stones is equal but the time will be different.

The time of stone thrown upward will be greater than that of downward.

Hence, The stone thrown upward lands farther away from the building.

Answer:

Another new technology in cancer treatment is Image Guided Radiation Therapy (IMGT), which also employs linear accelerators. IMGT allows for even more precise radiation treatment because it uses technology that can recognize the size and shape of the tumor within the body.

Explanation:

Answer:

B and D

Explanation:

Explanation:

The letter r stands for the radius of the sphere, which is the distance from the center of a sphere to its surface. The radius is exactly half of the diameter , which is the ...

mechanical energy

Explanation:

its right

A strong muscular system helps you in having good health for long life.

The muscular system is made up of specialized cells called as muscle fibers.

Their main function is contractibility. Muscles are attached to bones, internal organs as well as blood vessels which make movement better.

Almost all body movement is due to muscle contraction. If your willpower is strong, it benefits your whole body both now and in the future. Will power helps us strengthen our thought in mind and the urge to keep ourselves happy and healthy.

Thus, a strong muscular system helps you in keeping healthy for long.

Learn more about muscular system.

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Answer:

The difference in the amount of energy transferred by the two bulbs is 1200 J.

Explanation:

The energy transferred by the two lightbulbs can be calculated with the given equation:

[tex] E = P*t [/tex]

Where P is the power and t is the time

For the 60 W lightbulb:

[tex] E_{60} = P*t = 60 W*30 s = 1800 J [/tex]

For the 100 W lightbulb:

[tex] E_{100} = P*t = 100 W*30 s = 3000 J [/tex]

Hence, the difference in the amount of energy transferred is:

[tex] E_{t} = E_{100} - E_{60} = 3000 J - 1800 J = 1200 J [/tex]

Therefore, the difference in the amount of energy transferred by the two bulbs is 1200 J.

I hope it helps you!

The difference in the amount of energy transferred by the two bulbs during this time is 1200 J.

We know that

E = P*t

Here

P means the power and T means the time

So for 60W lightbulb, the energy should be

= 60*30

= 1800J

For 100 W, the energy should be

= 100*30

= 3000 J

So, the difference is

= 3000 -1800

= 1200 J

hence, The difference in the amount of energy transferred by the two bulbs during this time is 1200 J.

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Answer:

Please find the answer in the explanation

Explanation:

Friction is a force that opposes motion. One or two of the advantages of friction are break and ability of an object to walk.

Writing yes it is useful because when your writing because friction helps you see what your writing

ii. Rubbing. Yes, it is useful.

friction make it possible for two object to rub each other

iii. Skiing. No. It is not useful because With presence of friction, skiing will not be possible.

iv. Rotating a wheel No. It is not useful because Friction will oppose the rotation of the wheel.

Answer:8

Explanation: 134.4 divided by 16.8

Answer:

(a) 1.6 N/C, due east.

(b) 4 N/C, due east.

Explanation:

The force vector,[tex]\vec {F}[/tex] on the charge, q, in the electric field vector, [tex]\vec{E}[/tex], is

[tex]\vec {F}=\vec{E}q[/tex]

[tex]\Rightarrow \vec{E}=\frac{vec{F}}{q}\;\cdots(i)[/tex]

Let the unit vector towards east is [tex]\hat{i}[/tex], so the unit vector towards west is -

(a) Given that:

[tex]q=+25 \mu C[/tex],

[tex]\vec{F}=40.0 \mu N[/tex], due east

[tex]\Rightarrow \vec{F}=40.0 \mu N (\hat{i})[/tex]

From equation (i)

[tex]\vec{E}=\frac{40.0 \mu N (\hat{i})}{25 \mu C}=1.6(\hat{i}) N/C[/tex]

So, the magnitude of electric field is 1.6 N/C and the direction is towards east.

(b) Given that:

[tex]q=-10.0 \mu C[/tex],

[tex]\vec{F}=40.0 \mu N[/tex], due west

[tex]\Rightarrow \vec{F}=40.0 \mu N (-\hat{i})[/tex]

From equation (i)

[tex]\vec{E}=\frac{40.0 \mu N (-\hat{i})}{-10 \mu C}=-4(\hat{i}) N/C[/tex]

[tex]\Rightarrow \vec{E}=4(\hat{i}) N/C[/tex]

So, the magnitude of electric field is 4 N/C and the direction is towards the east.

Answer:C

Explanation:

She used 2 different amounts of salts so that was her mistake she should of used 1

Answer:

A.125

Explanation:

Its correct on Schoology.

Answer:

You will need to stop at least 20 m before you hit the elk.

Explanation:

Answer:

Explanation:

The mass of a substance when given the density and volume can be found by using the formula

From the question

volume = 78.0 mL

density = 1.85 g/mL

We have

mass = 78 × 1.85 = 144.3

We have the final answer as

Hope this helps you

Answer:

open system

Explanation:

The open system type of system is the ocean option (C) open system is correct.

It is defined as the energy that continuously comes from the sun. As we know, the sun is the greatest source of energy. The sun's radiation reaches the earth and can be utilized as heat energy.

The question is incomplete.

The complete question is:

Solar radiation is absorbed by the ocean. The absorbed energy evaporates water from the ocean. As water vapor (mass) enters the atmosphere it carries with it the heat used to evaporate the water and raises the air's humidity. What type of system is the ocean?

As we know,

An open system is one that responds to the movement of information, energy, and/or material between both the and its surroundings.

Thus, the open system type of system is the ocean if the water vapor (mass) enters the atmosphere it carries with it the heat used to evaporate the water and raises the air's humidity.

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Answer:

a spring tide occurs

Explanation:

ithe gravitational pull makes that tide happen

Answer:

Explanation:

The distance covered by an object given it's velocity and time taken can be found by using the formula

From the question

velocity = 4.2 m/s

time = 17 s

We have

distance = 4.2 × 17

We have the final answer as

Hope this helps you

Answer:

6.8ms²

Explanation:

a=v-u/t

a=57-40/2.5

a=17/2.5

a=6.8ms²

Answer:

the exact center of its mass

Answer:

HOW NEWTON'S LAWS RELATE TO REAL WORLD LIFE EXPERIENCE

Newton's law are very important because they tie into almost everything we see in everyday life. These laws tell us exactly how things move or sit still, like why you don't float out of bed or fall through the floor of your house. Newton's laws control how cars work, how water flows, how buildings don't fall down, and basically how everything around us moves.

EXAMPLE OF NEWTON'S LAW:

° First Law: Inertia

°Second Law: Force and Acceleration

°Third Law: Action and Reaction

HOW NEWTON'S LAW RELATE TO REAL LIFE EXPERIENCE

FIRST LAW (INERTIA) :

If you throw a rock straight up, it will not vary from its direction. Inertia enables ice skaters to glide on the ice in a straight line. If the wind is blowing, a tree's branches are moving. A piece of ripe fruit that falls from the tree will fall in the direction the wind is moving because of inertia.

SECOND LAW (FORCE AND ACCELERATION) :

The use of force in our everyday life is very common. We use force to walk on the road, to lift the objects, to throw a cricket ball, or to move a given body by some particular speed or direction. We are very familiar with the various effects of force. We can exert pull and push. And also When the car slows down. 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.

THIRD LAW (ACTION AND REACTION) :

For example, when you jump, your legs apply a force to the ground, and the ground applies and equal and opposite reaction force that propels you into the air. Engineers too apply Newton's third law when designing rockets and other projectile devices.