Do the data for the first part of the experiment support or
refute the first hypothesis? Be sure to explain your
answer and include how the variables changed in the
first part of the experiment.
Mechanical equivalent of heat

Answers

Answer 1

Answer:

Sample Response: The data for the first part of the experiment support the first hypothesis. As the height of the cylinder increased, the temperature of the water increased. At a greater height, the cylinder has more gravitational potential energy. This gravitational potential energy was completely converted to thermal energy, which increased the temperature of the water.

Explanation:

this the sample response from ED mechanical equivalent of heat lab.

Answer 2

Answer:

Sample response:

Explanation:

The data for the first part of the experiment support the first hypothesis. As the height of the cylinder increased, the temperature of the water increased. At a greater height, the cylinder has more gravitational potential energy. This gravitational potential energy was completely converted to thermal energy, which increased the temperature of the water.


Related Questions


Tarnishing of iron is similar to which of the following changes?
O Folding a paper
O Shredding a paper
Burning a paper
Dropping a paper

Answers

Answer:

Burning paper

Explanation:

The tarnishing of iron is a chemical process, and the only option that is a chemical process is Burning paper

An acceptable radiograph was taken using 40 mAs at 80 kVp at a distance of 60 inches. A second radiograph is requested at 40 inches. What mAs should be used to produce this radiograph with a 40-inch distance

Answers

Answer:

17.8 mAs

Explanation:

The exposure maintenance formula shows that as SID increases, intensity decreases, causing a decrease in film exposure and density. The mAs is directly proportional to the square of the distance. That is as mAs increases, distance increases, and vice versa, in order to maintain image receptor exposure. It is given by:

[tex]\frac{mAs_1}{mAs_2}=\frac{D_1^2}{D_2^2}[/tex]

Given that mAs₁ = original mAs = 40 mAs, D₁ original distance = 60 in, D₂ = new distance = 40 in, mAs₂ = new mAs

[tex]\frac{mAs_1}{mAs_2}=\frac{D_1^2}{D_2^2}\\\\mAs_2=\frac{mAs_1*D_2^2}{D_1^2}=\frac{40*40^2}{60^2}=17.8\\\\mAs_2=17.8\ mAs[/tex]

If a car drives 10 mph South, this is an example of a:
A. Displacement
B. Velocity
C. Distance
D. Speed

Answers

If a car drives 10 mph South, this is an example of a:

If a car drives 10 mph South, this is an example of a: Displacement

[DISPLACEMENT IS THE SHORT DISTANCE TRAVELLED BY A BODY AT A CERTAIN DIRECTION]

A velocity would be an automobile traveling south at 10 mph. Option B is correct.

What is velocity?

The change of displacement with respect to time is defined as velocity. velocity is a vector quantity. It is a time-based component. Its unit is m/sec.

If the direction is given quantity is a vector quantity. In the given data the direction is given, that's why a car drives 10 mph South, this is an example of a velocity.

Hence, option B is correct.

To learn more about the velocity, refer to the link: https://brainly.com/question/862972

#SPJ2

Presence of _______- in retina gives us night vision that is help us to see in dim light.Required to answer. Single choice. Immersive Reader (1 Point) cornea retina lens rods

Answers

Answer: Rods

Explanation:

The rod cells in the retina are the reason we are able to see at night and in dim light. They exist on the edges of the retina which is why they are also very useful for the peripheral vision of a human.

Rod cells number over 90 million in the eyes and although very useful for seeing in dimmer light, they are not very useful for color vision which is why humans see less colors in the dark.

In a second order lever system the force ratio is 2.5, the load is at the distance of 0.5m from the fulcrum find distance of effort if it losses are negligible​

Answers

Answer:

1.25 m

Explanation:

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

Force ratio = 2.5

Distance of load from the fulcrum = 0.5 m

Distance of effort =.?

The distance of the effort from the fulcrum can be obtained as illustrated below:

Force ratio = Distance of effort / Distance of load

2.5 = Distance of effort / 0.5

Cross multiply

Distance of effort = 2.5 × 0.5

Distance of effort = 1.25 m

Therefore, the distance of the effort from the fulcrum is 1.25 m

A 72 kg swimmer dives horizontally off a raft floating in a lake. The diver's speed immediately after leaving the raft is 3.8 m/s. If the time interval of the interaction between the diver and the raft is 0.25 s, what is the magnitude of the average horizontal force by diver on the raft?

Answers

Answer:

F = 1094.4 N

Explanation:

From impulse - momentum theorem, we now that ;

Impulse = momentum

Where;

Formula for impulse = force (F) × time(t)

Momentum = mass(m) × velocity(v)

Now, we are given;

Mass of swimmer; m = 72 kg

Speed; v = 3.8 m/s

Time; t = 0.25 s

Thus;

F × t = mv

F = mv/t

F = (72 × 3.8)/0.25

F = 1094.4 N

This value of force is the magnitude of the average horizontal force by diver on the raft.

Having the correct posture and the degree or severity of braking, acceleration and steering inputs have a direct result on the ability of a motorist to effectively address changes in __________?

Answers

Answer: Vehicle Balance

Explanation:

Vehicle balance simply means how the weight of a vehicle is distributed across its tires which connects to the road

It should be noted that there'll be a shift in the balance of a vehicle when the braking, acceleration, or turning bring about a scenario in which the weight of th vehicle moves from one area to another.

A rugby player passes the ball 6.8 m across the field, where the ball is caught at the same height as it left his hand. show answer No Attempt 33% Part (a) At what angle, in degrees above the horizontal, was the ball thrown if its initial speed was 12.0 m/s, assuming that the smaller of the two possible angles was used

Answers

Answer:

11.86°

Explanation:

Projectile motion is a form of motion where an object moves in parabolic path (trajectory). Projectile motion only occurs when there is one force applied at the beginning on the trajectory, after which the only interference is from gravity.

The range of an object experiencing projectile motion is given by:

R = u²sin(2θ) / g

where u is the initial velocity, θ is the angle with horizontal and g is the acceleration due to gravity

Given that R = 6.8 m, g = 10 m/s², u = 12 m/s.  

R = u²sin(2θ) / g

substituting:

6.8 = 13²sin(2θ) / 10

13²sin(2θ) = 68

sin(2θ) = 0.4024

2θ = sin⁻¹(0.4024)

2θ = 23.73

θ = 11.86°

If mass is the amount of MATTER present in the
object, will it be different on Earth and the moon?
No
Yes

Answers

Answer:

Yes it would be different on Earth and the moon

Answer:

yes

Explanation:

What is the relationship between Avogadro's number and a mole?
A. There are 6.02 x 1023 items in a mole, which equals Avogadro's
number
B. A mole is a smaller amount than Avogadro's number.
C. Avogadro's number is used to count particles, and a mole is used
to measure mass.
D. A mole applies to any item, but Avogadro's number is limited to
atoms.
SUBM

Answers

Answer:

A. There are 6.02 x 1023 items in a mole, which equals Avogadro's

number

Explanation:

The mole of a substance is

A Body is said to be in equilibrium when its:-
a) Acceleration is uniform
b) Speed is uniform
c) Speed and acceleration are uniform
d) Speed is uniform
I need the right answer. Please quick

Answers

Answer:

speed i uniform

Explanation:

if the speed is constant

Answer:

A

Explanation:

if it has a constant acceleration

How much energy does it take to boil water for pasta? For a one-pound box of pasta
you would need four quarts of water, which requires 15.8 kJ of energy for every degree Celsius (°C) of temperature increase. Your thermometer measures the starting
temperature as 48°F. Water boils at 212°F.


a. [1 pts] How many degrees Fahrenheit (°F) must you raise the temperature?
b. [2 pts] How many degrees Celsius (°C) must you raise the temperature?
c. [2 pts] How much energy is required to heat the four quarts of water from
48°F to 212°F (boiling)?

Answers

Answer:

a. 164°F

b. [tex]91.\overline 1 \ ^{\circ} C[/tex]

c. [tex]140.\overline 4[/tex] kJ

Explanation:

The starting temperature of the water, T₁ = 48F

The temperature at which the water boils, T₂ = 212°F

a. The difference between the initial and the boiling water temperature, ΔT = T₂ - T₁

Therefore;

ΔT = 212°F - 48°F = 164°F

The temperature by which he temperature must be raised, ΔT = 164°F

b. 48°F = ((48 - 32)×5/9)°C = (80/9)°C = [tex]8.\overline 8 \ ^{\circ} C[/tex]

212°F = ((212 - 32)×5/9)°C = 100°C

∴ ΔT = 100°C - [tex]8.\overline 8 \ ^{\circ} C[/tex] = [tex]9.\overline 1 \ ^{\circ} C[/tex]

c. The heat capacity of the water = The heat required to increase four quartz of water by 1 °C = 15.8 kJ

∴ The heat required to raise four quartz of water by [tex]9.\overline 1 \ ^{\circ} C[/tex], ΔQ = 15.8 kJ/°C × [tex]9.\overline 1 \ ^{\circ} C[/tex] = [tex]140.\overline 4[/tex] kJ.

Total amount traveled is

distance

displacement

Answers

Answer:

displacement

Explanation:

I hope ans will be right

why is oil denser than air​

Answers

Answer:

The molecules of oil are more packed together than those of air.

prove that vector addition obeys commutative and associative laws​

Answers

the order of vector addition doesn't affect the resultant vector and grouping or order of pair doesn't effect the sum.

A dog wishes to swim across a slow moving stream. The current velocity is 3.0m/s. The distance directly across the stream is 50m. If the dog point himself directly across the stream, it will take .....

Answers

Answer:

Time = 16.667 seconds

Explanation:

Given the following data;

Distance = 50 meters

Velocity = 3 m/s

To find the time it will take;

Velocity can be defined as the rate of change in displacement (distance) with time. Velocity is a vector quantity and as such it has both magnitude and direction.

Mathematically, velocity is given by the equation;

Velocity = distance/time

Making time the subject of formula, we have;

Time = distance/velocity

Time = 50/3

Time = 16.667 seconds

Which plate is the South American plate?

A
B
C
D

Answers

Answer: B

Explanation: I think that it is B.

In the hydraulic system depicted, the cylinder on the left has a diameter of 2 inches and the cylinder on the right has a diameter of 6 inches. If 100 lbs of force was applied to the cylinder on the left, what force would be exerted on the cylinder on the right

Answers

Answer:

F2 = 900 lbs

Explanation:

From pascal principle;

F1/A1 = F2/A2

Force on cylinder at left; F1 = 100 lbs

Diameter of cylinder at left; d1 = 2 inches

Diameter of cylinder at right; d2 = 6 inches

Formula for area of top of cylinder = πr²

Thus;

Area of top of left cylinder; A = π × 2² = 4π

Area of top of right cylinder; A = π × 6² = 36π

Thus;

100/4π = F2/36π

F2 = (36π × 100)/4π

F2 = 900 lbs

Noticing large amounts of algal growth in her small farm pond, a farmer adds about 20 grass carp to feed on the abundant algae and plants. After several years, the carp grow large, exceeding 20 pounds each in size. Late one summer, the farmer notices that the carp and most of the other fish are dead. The water also smells very bad. Which one of the following is the most likely explanation for the death of these fish?
A. the algae overgrew the pond and produced toxic levels of ozone
B. carbon dioxide released by the carp and algae eventually suffocated the fish in the pond
C. the large carp grew so large that they could not get enough oxygen
D. bacteria feeding on the large volume of carp feces depleted the oxygen

Answers

Answer:

D. bacteria feeding on the large volume of carp feces depleted the oxygen

Explanation:

In the context, it is given that in a small farm pond, the owner added 20 grass carp and feed them with the abundant plants and algae that is found on her pond. The carp grew large after many years but one summer the owner found the grass carps along with other fishes were dead.

The most possible explanation for the dead of the fishes in the pond because the bacteria feeds on the carp feces which depletes the dissolved oxygen present in the water. Thus the fishes could not breathe and were finally dead.

Therefore, the correct option is (D).

Compare the vertical and horizontal components of velocity for a ball launched at an angle on a level surface. How do the vertical and horizontal components of the ball's velocities change as it travels through the air?

Answers

Answer:

horizontal velocity remaing constan thorough out the motion but the vertical motion's velocity changes due to the gravity acting on it.

for everl 1 second the velocity decreases by 9.8 that is the gravity

A projectile is fired horizontally from a gun that is 58.0 m above flat ground, emerging from the gun with a speed of 170 m/s. (a) How long does the projectile remain in the air

Answers

Answer:

t = 3.44 s

Explanation:

We are given;

Fired from rest, and so; u = 0 m/s

Final speed; v = 170 m/s

Height above flat ground; y_o = 58 m

Height at starting point; y = 0 m

Thus, from Newton's equation of motion, we have;

y - y_o = ut - ½gt²

(since it's motion is against gravity)

Plugging in the relevant values, we have;

0 - 58 = 0 - (½ × 9.8 × t²)

-58 = -4.9t²

t² = 58/4.9

t = √(58/4.9)

t = 3.44 s

1.The distance moved by objects in a given interval of time can help us to decide which one is faster or slower. Do you agree with this statement?

Answers

Answer:

The rate of change of distance is defined as speed.

Explanation:

The speed is defined as the rate of change of distance.

Speed = distance/ time

When we know the distance and the time, we get the value of speed. So, e know that who is moving fast or slow.

hen a graph is pltted beteen the distance and time, the slope of the graph gives the value of speed. So, by checking the slopes, hoseslope ismore, the speed is more and thusit is moving faster.

So, i agree with the statement.  

Which of the following is a primary source?

Answers

The answer is C :), I think.

A scientific paper is the primary source. A primary source is an item, document, recording, or any other source. Option C is correct.

What is a scientific paper ?

Scientific papers are a specific sort of written work with certain characteristics: they are often published in a periodical called a journal, whose sole objective is to publish this type of work.

A primary source is an item, document, recording, or any other source of information created during the period being studied in the academic area of history.

A scientific paper is the primary source.

Hence,option C is correct.

To learn more about the scientific paper, refer:

https://brainly.com/question/1716162

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Describe los cambios en velocidad y aceleración durante las etapas de un salto en paracaídas. Salto desde avioneta

Answers

Answer:

Initially the acceleration is acceleration due to gravity and after that it is zero.

Explanation:

Describe the changes in speed and acceleration during the stages of a parachute jump. Jump from plane

As the person jump with the parachute and till the parachute is not opened, then in this condition, the acceleration is acceleration due to gravity due to which he moves in the downwards direction.

As the parachute is opened, the drag force of air and the buoyant force due to the air acts on the parachute in the upwards direction. So, the net acceleration is zero ad the force due to the gravity is balanced by the drag force and the buoyant force and thus the acceleration if zero and the person is safe.  

In the diagram, q1 = +2.00 x 10-5 C,
q2 = +3.80 x 10-6 C, and q3 = +5.30 x 10-5 C.
What is the electric potential energy, Ue, for
charge qy? Include the correct sign (+ or -).

Answers

Answer:

     U = 3.59 10⁻⁹ J

Explanation:

Electric potential energy is

             U = k ∑ [tex]\frac{q_iq_j }{r_i_j}[/tex]

in this case

            U = k (q₁q₂ / r₁₂ + q₁q₃ / r₁₃ + q₂q₃ / r₂₃)

the distances are

            r₁₂ = 1.15

            r₁₃ = 1.15 +2.88 = 4.03 m

            r₂₃23 = 2.88

we substitute

            U = 9 109 (2 10-5 3.8 10-6 / 1.15 + 2 10-5 5.30 10-5 / 4.03 + 3.8010-6 53 010-5 / 2.88)

             U = 9 109 (6.609 10-11 + 2.63 10-10 + 6.99 10-11)

            U = 9 109 (39,899 10-11)

            U = 3.59 10⁻⁹ J

Answer:

Q2 = 0.0346 J

Explanation:

I don't know what Q1 is but I did solve for Q2. I'm using this because no other question has been asked to solve for Q2 :)

: Một mặt phẳng vô hạn tích điện đều, mật độ σ = 4.10-9 C/cm2, đặt thẳng đứng trong không khí. Một quả cầu nhỏ có khối lượng 8 g, mang điện tích q = 10-8 C treo gần vào mặt phẳng, sao cho dây treo lúc đầu song song với mặt phẳng. Lấy g = 9,8m/s2. Khi cân bằng, dây treo quả cầu hợp với mặt phẳng 1 góc bằng bao nhiêu?

Answers

Answer:

The angle is 16 degree.

Explanation:

A uniformly charged infinite plane, density σ = 4.10-9 C/cm2, is placed vertically in air. A small ball of mass 8 g, with charge q = 10-8 C, hangs close to the plane, so that the string is initially parallel to the plane. Take g = 9.8m/s2 . In equilibrium, by what angle does the string hanging from the ball make an angle with the plane?

Surface charge density,   σ = 4 x 10^-9 C/m^2

charge, q = 10^-8 C

mass, m = 0.008 kg

Let the tension is the string is T and the angle is A.

[tex]T sin A = q E....(1)\\\\T cos A = m g .... (2)\\\\Divie (1) by (2)\\\\tan A =\frac{q E}{m g}\\\\tan A = \frac{10^{-8}\times 4\times 10^{-5}}{2\times 8.85\times 10^{-12}\times 0.008\times9.8}\\\\tan A = 0.288\\\\A = 16 degree[/tex]

1.how would you calculate the atomic mass of an atom of silver (at)?
2.the element chlorine (CI) has 17 protons and 17 electrons. What happens to an atom of chlorine (CI) if it gains an electron?
3. How does an atom differ from a molecule?
4. How do protons, neutrons, and electrons differ?
5. The element lithium (Li) has 3 protons and 3 electrons. The element fluorine (F) has 9 protons and 9 electrons. An atom of the element lithium (Li) transfers an electron to an atom of the element fluorine (F). Which type of bond results between The atoms, and what happens to the charges in each of the atoms?
6. Why do the minerals graphite and diamond look different even though they’re made from the same element, carbon (c)?

Answers

Answer:

1. atomic mass of silver 108

2. 18 electrons

3.an atom is the smallest particle of a substance that can exist by itself.

molecules are groups of atom

Explanation:

1. periodics table

2. gains electron, becomes negative

Answer:

To determine the atomic mass of silver, or any other element, add the number of protons and the number of neutrons together.

If a chlorine atom gains an electron, it will have an unequal number of protons and electrons, which makes it an ion. Because electrons are negatively charged, the ion will be negatively charged, also called an anion.

An atom is the smallest component of an element that retains all of the chemical properties of that element. A molecule is two or more atoms that have bonded together.

Protons and neutrons are found in the nucleus of an atom, while electrons are found in the area surrounding the nucleus of an atom. Protons have a positive charge, electrons have a negative charge, and neutrons have no charge.

Because the lithium atom loses a negatively charged electron, it becomes a positively charged ion, or cation. Because the fluorine gains a negatively charged electron, it becomes a negatively charged ion, or anion. A bond between an anion and a cation is an ionic bond.

Graphite and diamond look different because the carbon atoms bond to one another in different ways in the two minerals. This gives each mineral a unique lattice structure and, as a result, a different physical appearance.

A body has masses of 0.013kg and 0.012kg in oil and water respectively, if the relative density of oil is 0.875, calculate the mass of the body

Answers

Answer:

the mass of the body is 0.02 kg.

Explanation:

Given;

relative density of the oil, [tex]\gamma _0[/tex] = 0.875

mass of the object in oil, [tex]M_o[/tex] = 0.013 kg

mass of the object in water, [tex]M_w[/tex] = 0.012 kg

let the mass of the object in air = [tex]M_a[/tex]

weight of the oil, [tex]W_0 = M_a - 0.013[/tex]

weight of the water, [tex]W_w = M_a - 0.012[/tex]

The relative density of the oil is given as;

[tex]\gamma_0 = \frac{density \ of \ oil }{density \ of \ water} = \frac{W_0}{W_w} = \frac{M_a -0.013}{M_a -0.012} \\\\0.875 = \frac{M_a -0.013}{M_a -0.012}\\\\0.875(M_a - 0.012) = M_a - 0.013\\\\0.875M_a - 0.0105 = M_a -0.013\\\\0.875M_a - M_a = 0.0105 - 0.013\\\\-0.125 M_a = -0.0025\\\\M_a = \frac{0.0025}{0.125} \\\\M_a = 0.02 \ kg[/tex]

Therefore, the mass of the body is 0.02 kg.

Pls answer ASAP Which diagram shows a possible
sequence of steps in the research and development cycle? O A. New problem or discovery Engineering solution Development Research ОВ. Development Research Engineering solution New problem or discovery C. Research Development Engineering solution New problem or discovery OD. New problem or discovery Research Problem Engineering solution​

Answers

Answer:

A. New problem or discovery Engineering solution Development Research Explanation:

A possible  sequence of steps in the research and development cycle are  A. New problem or discovery Engineering solution Development Research​. In the  research and development cycle, the first step is the problem that a scientist observe. After that we have discover a solution for that problem through many research so the above materials are the possible sequence of steps in the research and development cycle.

What is the distance to school if it took bob 1 hour to get to it going at the speed of 1 km/h.

Answers

Answer:

1 km

Explanation:

Bob travels at one km/h and it takes him one hour to get there.

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