Answer:
Matter is matter. Particles are particles. Atoms are atoms. You can explain matter using particles and atoms.
JK!
Real Answer:
The term matter refers to anything that occupies space and has mass—in other words, the “stuff” that the universe is made of. An atom is the smallest unit of matter that retains all of the chemical properties of an element. Most atoms contain all three of these types of subatomic particles—protons, electrons, and neutrons.
Hope this helps!
why decomposition of sugar on heating is an irreversible change.
Answer:
The heat of formation of the products of the heating of sugar, which is caramel is higher and due to the new complexes formed such there is increased change in free energy between the products and the reactants of the sucrose decomposition by heating, making the reaction is irreversible
Explanation:
Sugar, also known as sucrose, C₁₂H₂₂O₁₁, is a disaccharide made up two monosaccharides, fructose, C₆H₁₂O₆, and glucose, C₆H₁₂O₆ joined together by a glycosidic covalent bond as such the molecule of sugar has one less molecule of H₂O than the fructose and the glucose it is made of which on heating the sugar the glycosidic bonds break and due to deficiency in the amount of H₂O the fructose and glucose combine with themselves to form caramel which has a much lower hydrogen and oxygen proportion such as C₂₄H₂₆O₁₃, which is darker and contains free radicals making caramel sticky.
Therefore, the heat of formation of the caramel is higher and due to the formation of the complexes there is increased change in free energy between the products than the reactants of the decomposition of sugar by heating, therefore, the reaction is irreversible.
An iron nail floats in mercury and sinks in water. Explain why?
Answer:
this is because mercury is more dense than iron nail, while water is less dense than the nail.
Explanation:
Answer:
Density
Explanation:
This is because of difference in densities of iron nail, mercury and water. Iron nail is less dense than mercury so it floats on mercury while it is more dense than water so it sinks!
state any two physical properties for believing that aluminium is a metal.
Answer:
amongst the properties that makes aluminium a metal is that it is malleable and ductile...and it has high melting and boiling points
I hope that helps
Explanation:
properties of metals include
1. high melting and boiling points
2 high densities
3 malleability and ductility
Which force best represents Fg
Answer:
The weight of barbell acting on a weight lifter is 80N.
Explanation:
Find average speed in
time interval t = 2 tot = 10s
Distance (m)
10+
8-
2
+ Time (s)
10
Answer: 3.75 m/s
Explanation:
Average speed is distance covered per time taken.
If the time interval is from t = 2 to t = 10s
Then, the time taken will be
t = 10 - 2 = 8s
Given that the distance covered are 10 + 8 - 2 + 10
Since distance is a scalar quantity, we will only consider the magnitude and not the direction.
Total distance = 10 + 8 + 2 + 10 = 30m
Average speed = total distance/time
Substitute total distance and time into the formula
Average speed = 30/8
Average speed = 3.75 m/s
What is the effect of the medium on the speed of the sound? In which medium sound travels more faster: air, solid, or liquid? Justify your answer?
Answer:
Sound travels fastest through solids. This is because molecules in a solid medium are much closer together than those in a liquid or gas, allowing sound waves to travel more quickly through it. In fact, sound waves travel over 17 times faster through steel than through air.
what is the current if 12 ohm and 4 ohm resistors are connected in parallel and 12 V potential difference is applied
The two resistors in parallel behave like 3 ohms.
I = V / R
Current = 12/3 = 4 Amps
1.what are some of the impacts of modern communication in our socio economic life?
2.how is possible to make a call to our relatives residing in other part of country ?explain?
Answer:
The impacts of modern communication in our socio economic life includes;
a) Staying connected
b) Carrying out business transaction
c) Exceeding boundaries
d) Overcoming weakness and disability
e) Reaching out to a wider audience
2. It is possible to make long distant call to our relatives in other part of the country by direct distance dialing (DDD)
Explanation:
The telecommunication service called direct distance dialing allows a caller to make a call to a location outside the area where they are calling without the assistance of an operator. To make a direct dialing call, a subscriber or caller will be required to include extra prefix digits to the original number than for numbers within hers or his particular local area code.
If a locomotive uses steam at
100°C, and dumps heat into air
at 22.0°C, what is the highest
possible efficiency it could have?
Answer:
79%
Explanation:
Data obtained from the question include the following:
Input temperature = 100°C
Output temperature = 22°C
Efficiency =.?
Next, we shall convert celsius temperature to Kelvin temperature.
This is illustrated below:
T(K) = T (°C) + 273
Input temperature = 100°C
Input temperature in Kelvin = 100°C + 273 = 373K
Output temperature = 22°C
Output temperature in Kelvin = 22°C + 273 = 295K
Finally, we shall determine the efficiency of the locomotive as follow:
Efficiency = output /input x 100
Output = 295K
Input = 373K
Efficiency =?
Efficiency = output /input x 100
Efficiency = 295/373 x 100
Efficiency = 79%
Therefore, the efficiency of the locomotive is 79%.
Answer:
The answer is .209
Explanation:
I am unable to show the work for this as I did it online but I can assure you it is correct
Wood has chemical energy, which can be used to generate thermal and radiant energy when burned in a fireplace. Which best explains what happens to the total amount of energy in this scenario?
Answer:In the case of burning wood, stored potential energy (in the form of chemical energy) in the log is released due to heating by other excited atoms. This chemical reaction is called combustion and requires oxygen. Combustion changes the potential chemical energy into kinetic energy in the form of heat.
Explanation:
Answer:
In the case of burning wood, stored potential energy (in the form of chemical energy) in the log is released due to heating by other excited atoms. This chemical reaction is called combustion and requires oxygen. Combustion changes the potential chemical energy into kinetic energy in the form of heat.
Last guy copied off my computer when i left room
Explanation:
answer the following question
Answer:
A) OA, AB, BC
B) 25m/s^2
C) see explanation
D) 25
E) Rest
Explanation:
From the Velocity time graph shown:
The positive slope = OA ; This is positive because, it is the point of uniform acceleration on the graph.
Constant slope = AB, the slope here is constant because, AB on the graph is the point of constant velocity.
-ve slope = BC
B) Acceleration of body in path OA.
Acceleration = change in Velocity / time
Acceleration = (150 - 0) / 6
Acceleration = 150/6 = 25m/s^2
C) Path AB is Parallel to the because it marks the period of constant velocity (that is Velocity does not increase or decrease during the time interval).
D) Length of BC
BC corresponds to the distance moved, that velocity / time
Velocity = 150 ; time = 6
Therefore Distance (BC) = 150/6 = 25
E.) Velocity =0 ; Hence body is at rest
Does the earths magnetic field change with time?
Answer:
As per the fossil fuel records, magnetic field reversal does not impact living beings. It will take almost a century for the poles to complete the shift. Meanwhile, the earth is left with almost zero magnetic field.
Which describes reproducibility? The ability of data to be published. The ability of data to be duplicated. The ability of data to be changed. The ability of data to be invalidated.
Answer:
the ability of data to be duplicated well described reproducibility
Explanation:
Reproducibitity of a data is the ability of a data to be produced in multiple times using the same procedure. It is used to test how precise a data is and it's usually known as standard deviation
Reproducibility is the closeness of the understanding between the consequences of measurements of the equivalent measurand did with a similar procedure depicted in the relating logical proof (for example a distribution in a companion surveyed diary).
Answer:
the ability of data to be duplicated well described reproducibility
A bus accelerates at -0.5 m/s2 for 12.5 seconds . If the bus had an initial speed of 31 m/s, what is its new speed? A. 12.25m/s B. 37.25m/s C. 24.75m/s D. 6.25m/s
Answer:
37.5m/s
Explanation:
a=(v-u)/t
0.5 = (v - 31) / 12.5
v - 31 = 0.5 x 12.5
v - 31 = 6.25
V = 6.25 + 31
v = 37.25m/s
a ball is rolling along a ground with a velocity of 10m/s and comes to rest after 8s.what is its acceleration
Answer:
-1.25 m/s²
Explanation:
Use the formula a=(v-u)/t,
acceleration a = unknown
final velocity v= 0 m/s (rest)
initial velocity u = 10m/s
time t = 8s
a = (0-10)/8
a = -1.25 m/s²
Infrared waves have higher frequencies than microwaves. Which statement best compares the energy of these two types of waves?
Each infrared photon carries more energy than any microwave photon.
(If this statement is not one of the choices, then it's really sad that you couldn't show us the list of choices to select from.)
Answer:
The energy of infrared waves is more than that of microwaves.
Explanation: Just completed on Edmentum
Please HELP!!! I will give brainliest to whoever gives honest help!!! A 500 kg satellite experiences a gravitational force of 3000 N, while moving in a circular orbit around the earth. Determine the radius of the circular orbit. Determine the speed of the satellite. Determine the period of the orbit.
Given that,
Mass of satellite = 500 kg
Gravitational force = 3000 N
We need to calculate the radius of the circular orbit
Using formula of gravitational force
[tex]F_{g}=\dfrac{GMm}{(R+h)^2}[/tex]
Where, G = gravitational constant
R = radius of earth
h = radius of the circular orbit
M = mass of earth
m = mass of satellite
Put the value into the formula
[tex]3000=\dfrac{6.67\times10^{-11}\times500\times6\times10^{24}}{(6.4\times10^{6})^2+h^2}[/tex]
[tex]h^2=\dfrac{6.67\times10^{-11}\times500\times6\times10^{24}-3000\times(6.4\times10^{6})^2}{3000}[/tex]
[tex]h=\sqrt{\dfrac{6.67\times10^{-11}\times500\times6\times10^{24}-3000\times(6.4\times10^{6})^2}{3000}}[/tex]
[tex]h=5073460.35\ m[/tex]
[tex]h=5.1\times10^{6}\ m[/tex]
(II). We need to calculate the speed of the satellite
Using formula of velocity
[tex]v=\sqrt{\dfrac{GM}{r}}[/tex]
Put the value into the formula
[tex]v=\sqrt{\dfrac{6.67\times10^{-11}\times6\times10^{24}}{5.1\times10^{6}}}[/tex]
[tex]v=8858.36\ m/s[/tex]
[tex]v=8.8\times10^{3}\ m/s[/tex]
[tex]v=8.8\ km/s[/tex]
(III). We need to calculate the period of the orbit
Using formula of time period
[tex]T=2\pi\sqrt{\dfrac{r^3}{GM}}[/tex]
Put the value into the formula
[tex]T=2\pi\sqrt{\dfrac{(5.1\times10^{6})^3}{6.67\times10^{-11}\times6\times10^{24}}}[/tex]
[tex]T=3617.40\ sec[/tex]
[tex]T=1.00\ hr[/tex]
Hence, (I). The radius of the circular orbit is [tex]5.1\times10^{6}\ m[/tex]
(II). The speed of the satellite is 8.8 km/s.
(III). The period of the orbit is 1.00 hr.
On which body would a 10 kg lamp have the most gravitational potential energy when lifted to height of 2 m? A) Earth B) Mars C) Neptune D) Uranus
Answer: C.) Neptune
Explanation:
The Gravitational Potential Energy (GPE) of a body is calculated using the formula :
GPE = mgh
Where m = mass of the body
g = acceleration due to gravity
h = distance above a surface
Mass = 10kg
h = 2m
Using the formula :
GPE of lamp on Earth: g = 9.8
GPE = 10 × 9.8 × 2 = 71.8J
GPE of lamp on Mercury: g = 3.59
GPE = 10 × 3.59 × 2 = 196J
GPE of lamp on Mars: g = 3.7
GPE = 10 × 3.7 × 2 = 74J
GPE of lamp on Neptune: g = 14.07
GPE = 10 × 14.07 × 2 = 281.4J
GPE of lamp on Uranus: g = 9
GPE = 10 × 9 × 2 = 180J
GPE of lamp on Pluto: g = 0.42
GPE = 10 × 0.42 × 2 = 8.4J
Neptune has the highest gravitational potential energy as the value of acceleration due to gravity acting on objects is highest on Neptune.
Answer:
The correct option is;
C) Neptune
Explanation:
The force of gravity is given by the equation;
[tex]F_g = G\dfrac{m_1m_2}{r^2} = m_2 \times g[/tex]
Where:
m₁ = Mass of the planet
m₂ = Mass of the body = 10 kg
r = The distance between the body and the planet = 2 m
g = Gravitational acceleration on the planet
G = Gravitational constant
Given that the potential energy, PE = m × g × h
We have that,
[tex]PE = m_2 \times g \times (r + 2) = G\dfrac{m_1m_2}{r^2} \times (r + 2) \approx G\dfrac{m_1m_2}{r^2} \times r = G\dfrac{m_1m_2}{r}[/tex]
Therefore, the gravitational potential energy is directly proportional to the acceleration of gravity, such that the body will have the most gravitational potential energy in the planet with the highest acceleration due to gravity which is Neptune with acceleration due to gravity of 14.07 m/s².
Un proyectil es lanzado horizontalmente desde una altura de 12 metro con una velocidad de 80 m/sg. a.Calcular el tiempo de vuelo b. Su alcance horizontal y velocidad de impacto contra el suelo.
Answer:
t= 1,56 s , x= 124,8 m , v = (80 i^ - 15,288 j ) m/s
Explanation:
Este es un ejercicio de lanzamiento proyectiles, comencemos por encontrar el tiempo que tarda en llegar al piso
y = y₀ + [tex]v_{oy}[/tex] t – ½ g t²
en este caso la altura inicial es y₀= 12 m y llega a y=0 , como es lanzado horizontalmente la velocidad vertical es cero (v_{oy}=0)
0 = y₀ – ½ g t²
t= √ (2 y₀/g)
calculemos
t= √ ( 2 12 / 9,8)
t= 1,56 s
El alcance del proyectil es la distancia horizontal recorrida
x = v₀ₓ t
x = 80 1,56
x= 124,8 m
La velocidad de impacto cuando toca el suelo
vx = v₀ₓ = 80 ms
[tex]v_{y}[/tex] = v_{oy} – gt
v_{y} = - 9,8 1,56
v_{y} = - 15,288 m/s
la velocidad es
v = (80 i^ - 15,288 j ) m/s
Traducttion
This is a projectile launching exercise, let's start by finding the time it takes to reach the ground
y = y₀ + v_{oy} t - ½ g t²
in this case the initial height is i = 12 m and it reaches y = 0, as it is thrown horizontally the vertical speed is zero ([tex]v_{oy}[/tex] = 0)
0 =y₀I - ½ g t²
t = √ (2y₀ / g)
let's calculate
t = √ (2 12 / 9.8)
t = 1.56 s
Projectile range is the horizontal distance traveled
x = v₀ₓ t
x = 80 1.56
x = 124.8 m
Impact speed when it hits the ground
vₓ = v₀ₓ = 80 ms
v_{y} = v_{oy} - gt
v_{y} = - 9.8 1.56
v_{y} = - 15,288 m / s
the speed is
v = (80 i ^ - 15,288 j) m / s
Tsar Nicholas II and Tsarina Alexandra were the Roma
place in 1917. During this revolution, Tsar Nicholas Il v
killed. The remains of two of the Tsar and Tsarina's chi
people came forward who claims to be the missing Ro
Alexei?
O DNA technology
O STR analysis
O mtDNA analysis
O Y-chromosome analysis
A company plans to build a new mega store next to a wetland. Which of the following should it do to make sure it has scientific knowledge to inform its decision? Hire an environmental company to study the wetland and give recommendations of how to prevent flooding Ask a developer to build a new housing development next to the store site Have the city council review the architectural plans Conduct a survey to see how often people in the neighborhood shop
Answer:
The correct option is;
Hire an environmental company to study the wetland and give recommendations of how to prevent flooding
Explanation:
Due to the environmental importance of wetlands which are important plant and animal habitats and a source of filtration of reserve of water moving into other surface water bodies and underground aquifers, serving also as a buffer zone to prevent erosion and flooding during heavy rain storms, proper, detailed and well informed environmental considerations are required
As such an environmental consultant services is needed for site analysis, appraisal and recommendation will be required to fast track the process of obtaining a permit.
Answer:
A
Explanation:
write a story that ends with poor no friend
Answer:
Writing of a story that ends with the character becoming poor with no friends.
Explanation:
There was a young girl who believed that all things revolve around her. She had the money, the power, the family, and the beauty to ensure she was the center of attention. She would always be the main focus, everywhere she goes.
But there came a time when she had a major misfortune. Her family had come upon unfortunate times. They are going to lose their money and may even be jailed for embezzlement. It was true that she had no idea what her parents had done but she was also so familiar with the 'princess' lifestyle that she did not know how to downgrade her lifestyle. And so, when this misfortune happened, she was unsure how to react. She also assumed that her friends will be there for her. Little did she know everyone was just after her wealth and influence and had nothing to do with genuine friendship.
In a few months, their family position moved from top to bottom, which everyone found hard to accept. She had to maintain her status while at the same time try to live up with that without losing her circle. But as rumors spread fast and she wasn't able to spend the way she would normally send, she eventually experienced a dwindled friend circle. And in about a year, she had lost all of her friends, couldn't even convince someone to stay with her faithfully and worse of all, she was also poor, the very status she had degradingly taunted other people with.
At the equator, near the surface of the Earth, the magnetic field is approximately 50.0 μT northward, and the electric field is about 100 N/C downward in fair weather. Find the gravitational, electric, and magnetic forces on an electron in this environment, assuming that the electron has an instantaneous velocity of 8.50 ✕ 106 m/s directed to the east.
Answer:
A) F_g = 8.9278 × 10^(-30)
B) F_e = 1.6 × 10^(-17) N upwards
C) F_m = 6.8 × 10^(-17) N downwards
Explanation:
A) Formula for gravitational force is;
F_g = m_e × g
m_e is mass of electron = 9.11 x 10^(-31) kg
F_g = 9.11 x 10^(-31) × 9.8
F_g = 8.9278 × 10^(-30) N downwards
B) Formula for Electric force is;
F_e = qe
q is charge on electron = 1.6 × 10^(-19) C
E is electric field = 100 N/C
F_e = 1.6 × 10^(-19) × 100
F_e = 1.6 × 10^(-17) N upwards
C) Magnetic force is given by the formula;
F_m = qVB
q is charge on electron = 1.6 × 10^(-19) C
V is velocity given as 8.50 × 10^(6) m/s
B is magnetic field = 50.0 μT = 50 × 10^(-6) T
F_m = 1.6 × 10^(-19) × 8.50 × 10^(6) × 50 × 10^(-6)
F_m = 6.8 × 10^(-17) N downwards
in travelling 65cm along the barrel of a rifle a bullet accelerates from rest to 230 m/s. Find the acceleration and the time the bullet is in the barrel.
Answer:
[tex]2ax=v_{2}^{2}-v_{1}^{2}\\2a(\frac{65}{100})=230^{2}-0^{2}\\a=40692\frac{4}{13}m/s^{2}\\\\x=\frac{1}{2} at^{2}\\\frac{65}{100}=\frac{1}{2}(40692\frac{4}{13})t^{2}\\t=0.0101896s[/tex]
I've written all the needed equations for you. All you have to do is some replacements.
Please do not hesitate to ask further questions.
160 km
Hope this helps....
A man is dragging a trunk up the loading ramp of a mover's
truck. The ramp has a slope angle of 20.00, and the man pulls
upward with a force of magnitude 375 N whose direction makes
an angle of 30.0° with the ramp. Find the horizontal and vertical
components of the force F.
Answer:
Horizontal component = 241 N
Vertical component = 287 N
Explanation:
Given:
Force = F = 375 N
Referring to diagram attached, the force F is making an angle
theta = 20+30 = 50 with the horizontal.
Horizontal component = F*cos(theta) = 375*0.64278 = 241 N
Vertical component = F*sin(theta) = 375*0.76604 = 287 N
The vertical component of the force is 187.5 N and the horizontal component of the force is 324.8 N.
A vector is a any quantity that has both magnitude and direction. We can resolve any vector into its vertical and horizontal components. The vertical component of a vector such as force is F sin θ while the horizontal component of the force is F cos θ.
Given the following information from the question;
F = 375 N
θ = 30.0°
Vertical component(Fy) = 375 N sin 30.0° = 187.5 N
Horizontal component (Fx) = 375 N cos 30.0° = 324.8 N
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La luz pasa del medio A al medio B formando un ángulo de 35° con la frontera horizontal entre ambos. Si el ángulo de refracción también es de 35°, ?cuál es el índice de refracción relativo entre los dos medios?
Answer:
Índice de refracción entre los dos medios = 1,43
Refractive index between the two media = 1.43
Explanation:
El índice de refracción entre dos medios se explica mejor entendiendo primero la refracción.
Cuando las olas se mueven de un medio a otro, a menudo experimentan un cambio de dirección con respecto al medio en el que viajan.
Por lo tanto, el índice de refracción se expresa como el seno del ángulo de incidencia dividido por el seno del ángulo de refracción.
El seno del ángulo de incidencia y la refracción utilizados en esta fórmula de índice de refracción se miden respectivamente con respecto a la vertical.
En esta pregunta Ángulo de incidencia = 35° a la horizontal = (90° - 35°) a la vertical = 55° a la vertical.
Ángulo de refracción = 35°
Índice de refracción entre los dos medios
= (Sin 55°) ÷ (Sin 35°)
= 0.8192 ÷ 0.5736
= 1.428 = 1.43 a 2 d.p.
¡¡¡Espero que esto ayude!!!
English Translation
The light passes from medium A to medium B at an angle of 35 ° with the horizontal border between the two. If the angle of refraction is also 35 °, what is the relative refractive index between the two media?
Solution
The refractive index between two media is best explained by first understanding refraction.
When waves move from one medium to another, they often experience a change in direction with respect to the medium in which they are travelling.
Hence, refractive index is expressed as the sine of angle of incidence dibided by the sine of angle of refraction.
The sine of angle of incidence and refraction used in this refractive index formula are both respectively measured with respect to the vertical.
In this question,
Angle of incidence = 35° to the horizontal = (90° - 35°) to the vertical = 55° to the vertical.
Angle of refraction = 35°
Refractive index between the two media
= (Sin 55°) ÷ (Sin 35°)
= 0.8192 ÷ 0.5736
= 1.428 = 1.43 to 2 d.p.
Hope this Helps!!!
A small block slides down an incline with a constant acceleration. The block is released from rest at the top of the incline. After it travels 5 m to the bottom its speed is 5 m/s. What is the speed, in m/s, of the block when it had traveled only 2.1 m from the top
Answer:
v = 3.24 m/s
Explanation:
Since we don't have time, we can use the formula;
(Final distance - initial distance)/time = (initial velocity + final velocity)/2
Thus;
(x_f - x_i)/t = ½(v_xi + v_xf)
We are given;
x_i = 0 m
x_f = 5 m
v_xi = 0 m/s
v_xf = 5 m/s
Thus, plugging in the relevant values;
(5 - 0)/t = (0 + 5)/2
5/t = 5/2
t = 2 s
Using Newton's first law of motion, we can find the acceleration.
v = u + at
Applying to this question;
5 = 0 + a(2)
5 = 2a
a = 5/2
a = 2.5 m/s²
To get the speed, in m/s, of the block when it had traveled only 2.1 m from the top, we will use the formula;
v² = u² + 2as
v² = 0² + 2(2.5 × 2.1)
v² = 10.5
v = √10.5
v = 3.24 m/s
I NEED HELP PLEASE, THANKS! :)
Three 15.0-W resistors are connected in parallel across a 30.0-V battery. Please show all work.
a) Find the current through each branch of the circuit.
b) Find the equivalent resistance of the circuit.
c) Find the current through the battery.
Answer:
Take a look at the attachment below.
Explanation:
Current for each branch of the circuit is 2A and equivalent resistance of the circuit will be 5 ohms. The current through the battery is 6A.
What is Current?An electric current is defined as a stream of charged particles, such as electrons or ions, moving through an electrical conductor or space, which is described as the flow of electric charge through a surface or in a control volume.
Current is expressed as:
I=V/R
Where, I is the current
V is the voltage
R is the resistance
For above given information,
Since all resistors have the same resistance, it would be fine to find only 1 branch as the current would be the same for all branches.
[tex]I=V/R_1[/tex]
I= 30/15= 2 A
Equivalent resistance for parallel circuits is the sum of reciprocals of each resistor.
[tex]1/R= 1/R_1+ 1/R_2+ 1/R_3[/tex]
1/R= 1/15+ 1/15 + 1/15
1/R=3/15
R = 15/3= 5 ohms
I = V/R
Where I is current, V is voltage and R is the equivalent resistance
=> I = 30/5
=> I = 6 A
Thus, current for each branch of the circuit is 2A and equivalent resistance of the circuit will be 5 ohms. The current through the battery is 6A.
Learn more about Current, here:
https://brainly.com/question/16979805
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The volume of a piece of metal of a mass 6 gram is 15cm3. What is the density of the metal piece?
Answer:
0.4 g/cm^3
Explanation:
The density of an object can be found using the following formula.
d= m/v
where m is the mass and v is the volume.
The mass of the metal is 6 grams and the volume is 15 centimeters^3
m=6 g
v= 15 cm^3
Substitute these into the formula.
d= 6 g/ 15 cm^3
Divide 6 g by 15 cm^3 (6/15=0.4)
d= 0.4 g/ cm^3
The density of the metal is 0.4 grams per cubic centimeter.
Density = (mass) / (volume)
Density = (6 g) / (15 cm³)
Density = (6/15) (g/cm³)
Density = 0.4 g/cm³
This 'metal' has less than half the density of water, and it floats on water ! It cannot be of Earthly origin, and must have been dropped here by aliens.
Either that, or else the metal has been hammered and stretched and beaten out and shaped so that it has an artificially large volume ... something like the way sailing ships are made out of thick plates of steel.
the weight of a body will be zero during free fall. Why?
Answer:
The apparent weight of a freely falling body is zero. When a body falls freely, it is falling with an acceleration =g. Thus the entire gravitational force acting on it is utilized in accelerating it and hence its weight is not felt.