Contact and Non-contact Forces Assignment
Now that you have learned about forces, complete and submit the following assignment.

For the following situations, describe the contact and non-contact forces that are involved.

Situation
Contact Force(s)
Non-Contact Force(s)
A book sitting on a shelf






A soccer player kicking a ball; the ball soaring through the air and landing on the ground






A hiker in the woods reading her compass to determine which direction to go






A child on a sled; first, the child is sitting at the top of the hill, waiting his turn; then, the child pushes off and slides down the hill, eventually coming to a stop.

Answers

Answer 1

Answer:

I didn't know the subject but I researched and understood so...here goes!!

A book resting on a shelf: contact force- reaction force

                                          non contact force: gravitational force

Soccer ball- contact force- air resistance

                   non contact force- gravitational force

Compass- contact force- reaction force

                non contact force- magnetic force

child on sled- contact force- friction

                      non contact force- gravitational force

Explanation:


Related Questions

Billy needs to get to Pigeon Forge, that is 58.25 miles away from where he is. He is driving at 62.5 mi/hr. How long will it take him to get there?

Answers

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

Jordan wants to know the difference between using a 60-W and 100-W lightbulb in her lamp. She calculates the energy it would take to use each bulb for 30 s by using this equation: Power = Energy transferred (J)/time (s) What is the difference in the amount of energy transferred by the two bulbs during this time?

Answers

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.

Calculation of the difference in the amount of energy:

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.

Learn more about energy here: https://brainly.com/question/24401678

How far can a dragonfly get if it flies 17 seconds at a speed of 4.2 m/s

Answers

Answer:

The answer is 71.4 m

Explanation:

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

distance = velocity × time

From the question

velocity = 4.2 m/s

time = 17 s

We have

distance = 4.2 × 17

We have the final answer as

71.4 m

Hope this helps you

what is an objects center of gravity
A) the exact center of its mass
B) the part that is closest to earth
C) any part of an object , as long as it has mass
D) all of the above

Answers

Answer:

the exact center of its mass

The Center of gravity is the average location of the weight of an object. We can completely describe the motion of any object through space in terms of the translation of the center of gravity of the object from one place to another, and the rotation of the object about its center of gravity if it is free to rotate. So the Answer is C.

A car is traveling at 30 m/s when the driver spots an Elk in the road 50 m ahead.

Determine the necessary minimum acceleration to stop just in time. Draw the three

Graphs neatly.

Answers

Answer:

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

Explanation:

a) We produce a diffraction pattern on a viewing screen by means of a long narrow slit illuminated by blue light. Does the pattern expand away from the bright center (the maxima and minima shift away from the center) or contract toward it if we I. switch to yellow light or II. Decrease the slit width? 02 x 02 = 04 Marks

Answers

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.

what is the molar mass of cobalt chloride?

A. 271.17 grams
B. 94.38 grams
C. 129.83 grams
D. 95 grams

Answers

Answer:

The answer is C. 129.83 grams

Answer is C. 129.83 grams

A charged cell phone has chemical energy stored in its battery. As you use your phone, the amount of chemical energy in the battery decreases. Why is this not a violation of the first law of thermodynamics?

Answers

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".

In a charged cell phone, the chemical energy is being transformed to electrical energy as you use it. A phone cannot directly be powered with chemical energy. The energy transformation to electrical energy makes it possible to use the phone. In this process no energy is lost nor created. But simply, energy is transformed.

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

Conversion of energy:

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.

It may seem like the first law of thermodynamics is being violated here as the chemical energy of the cell is decreasing but that's not the case.It is because the chemical energy in the battery is being converted into electrical energy.There is no energy being created or lost here. It is a simple conversion of energy from one form to another.The conservation of energy is being followed as the loss of chemical energy is equal to the gain in electrical energy of the system.

Learn more about energy conversion:

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One mole of copper at a uniform temperature of 0° C is placed in thermal contact with a second mole of copper which, initially, is at a uniform temperature of 100° C. Calculate the temperature of the 2-mole system, which is contained in an adiabatic enclosure, when thermal equilibrium is attained. Why is the common uniform temperature not exactly 50° C? How much thermal energy is transferred, and how much entropy is produced by the transfer? The constantpressure molar heat capacity of solid copper varies with temperature as cp = 22.64 + 6.28×10−3T J/mole K

Answers

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.

Students in a lab were given an unknown sample to find the density of. The volume of the unknown sample was 16.8 ml, the calculated mass of the unknown sample was 134.4. What is the density of the unknown sample?
Note: You only have to fill in the numerical answer.

Answers

Answer:8

Explanation: 134.4 divided by 16.8

How would you measure and compare the size of two balls

Answers

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 ...

If your
is strong, it benefits your whole body both now and in the future. A strong muscular system helps you in three main ways:

1. You will have better long term health.

2. You will have better performance in activities.

3. You will have improved appearance.

Answers

this answer is a because if you prepare earlier for good health it will help you stay healthier

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

What is muscular system?

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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Suppose you want to determine the electric field in a certain region of space. You have a small object of known charge and an instrument that measures the magnitude and direction of the force exerted on the object by the electric field. (a) The object has a charge of +25.0 μC and the instrument indicates that the electric force exerted on it is 40.0 μN, due east. What are the magnitude and direction of the electric field? E = (b) What are the magnitude and direction of the electric field if the object has a charge of -10.0 μC and the instrument indicates that the force is 40.0 μN, due west? E = (Chp18,p13GO)

Answers

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.

The average speed of a car that travels 500 km in 5 hours is

Answers

Answer:

100km/h

Explanation:

500km/5 = 100km per hour

please help me :/
Describe how Newton's laws relate to real world life experiences. Give an
example of each law and how it relates to real life experiences.

Answers

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.

What is a new technology that is now being used to treat cancer? ​

Answers

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:

What is a disadvantage of the inefficiency of cars?
Group of answer choices

Tire wear

low speeds of cars

time it takes to get somewhere

air pollution
someone help please

Answers

The answer is air pollution

Sound energy: chemical energy: mechanical energy:

Answers

mechanical energy

Explanation:

its right

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?

Answers

Answer:

open system

Explanation:

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

What is solar energy?

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?

isolated systeminteractive systemopen systemclosed system


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.

Learn more about solar energy here:

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This athlete loads a sled to a combined mass of 90.0 kg, and drags the sled with a force of 258 N at an angle of 15.0° across a surface with a coefficient of kinetic friction of 0.250. What is the approximate acceleration of the sled?

Group of answer choices

Answers

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

mastering physics Two stones are launched from the top of a tall building. One stone is thrown in a direction 30.0 ∘ above the horizontal with a speed of 18.0 m/s ; the other is thrown in a direction 30.0 ∘ below the horizontal with the same speed

Answers

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.

19. A sample of an element has a volume of 78.0 mL and a density of 1.85 g/mL. What is the mass in grams of the sample? identify the information you are given.
A. 42.2 g
B. 76.2 g
sC. 144 g​

Answers

Answer:

The answer is 144 g

Explanation:

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

mass = Density × volume

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

144 g

Hope this helps you

As the spaceship travels upward in the sky, some of its kinetic energy will be lost to the universe due to ?

a) Friction
b) Chemical Potential Energy
c) Temperatures decreasing as altitude increases

Answers

Answer:

Friction !!!

Explanation:

define heat...and angle of friction?​

Answers

Explanation:

Heat is the form of energy that is transferred between systems or objects with different temperatures.....

Angle of friction : The angle which the resultant of force of limiting friction F and normal reaction R makes with direction of normal reaction R is called angle of friction...

physics the angle of a plane to the horizontal when a body placed on the plane will just start to slide. The tangent of the angle of friction is the coefficient of static friction.

A car traveling at 40 m/s accelerates to 57 m/s in 2.5 seconds. What is the acceleration of the car?

Answers

Answer:

6.8ms²

Explanation:

a=v-u/t

a=57-40/2.5

a=17/2.5

a=6.8ms²

Describe what happens to the gravitational force when the Sun, Earth and Moon
are in a line.

Answers

Answer:

a spring tide occurs

Explanation:

ithe gravitational pull makes that tide happen

2. In the activities below indicate if friction is useful or not useful? Explain your answer. i. Writing yes it is useful because when your writing because friction helps you see what your writing ii. Rubbing iii. Skiing iv. Rotating a wheel

Answers

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.

Devin investigated whether salt reduces the boiling point of water. She poured 1 gallon of 18 degrees Celsius (°C) water into a pot and added 2 cups of salt to it. Devin heated it over a fixed flame and measured the temperature when the water reached a rolling boil. She repeated the experiment with 1 gallon of water and 4 cups of salt under identical conditions. Where did Devin make a mistake in her experimental design?


She did not boil a pot of water without salt.


She waited until the water reached a rolling boil.


She used different amounts of salt in the two pots.


She did not heat the pots of water at the same time.

Answers

Answer:C

Explanation:

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

If a car travels 300 m in 20 seconds how fast is it going?

Answers

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.

how many bulldogs to beat 43 dragonss if each bulldog can beat 10 dragons​

Answers

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

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