Answer:
The density of brass is approximately 8,261.73 kg/m³
Explanation:
The percentage composition by mass of brass is given as follows;
The percentage by mass of copper = 67%
The percentage by mass of zinc = 33%
The density of copper, ρ₁ = 8.96 g/cm³
The density of zinc, ρ₂ = 7.133 g/cm³
Therefore, where we have, m = 100 g of brass, we have;
The mass of copper, m₁ = 67 g
The volume of copper, V₁ = m₁/ρ₁
∴ V₁ = 67 g/(8.96 g/cm³) ≈ 7.47767857 cm³
The volume of zinc, V₂ = m₂/ρ₂
∴ V₂ = 33 g/(7.133 g/cm³) ≈ 4.62638411 cm³
The volume of the brass, V = V₁ + V₂
V = 7.47767857 cm³ + 4.62638411 cm³ ≈ 12.104 cm³
The density of brass, ρ = m/V
∴ ρ = 100 g/(12.104 cm³) ≈ 8.26 g/cm³
The density of brass, ρ ≈ 8.26 g/cm³ = 8,261.73 kg/m³
The waste product of photosynthesis is
Answer:
oxygen
Plants need to excrete excess carbon dioxide and oxygen. Carbon dioxide is a waste product of aerobic respiration in plant cells. Oxygen is a waste product of photosynthesis .
Explanation:
yw!
Scientists have developed a new type of solar cell with an efficiency of over 40 %.
The efficiency of the solar cell was confirmed independently by other scientists.
Suggest why it was important to confirm the efficiency independently.
Answer:
According to Carl Sagan's Baloney Detection Kit notes
"Whenever possible there must be independent confirmation of the facts"
Independent confirmation by other scientist is to ensure that the observation of the over 40% efficient solar panel is repeatable
It is also important to avoid accepting the given mandates at face value and accepting that the scientist considered all factors when taking the results or that the original developers has assigned others to check their findings before the introduction of the new type of solar cell
Explanation:
Two cups having different liquids at a temperature of 20°c and 68°c lose heat energy to the environment. To measure the temperature difference between the two cups of liquid, you would use a ____
Answer:
youd use a thermometer. this can be used to measure the temperature of a solid such as food, a LIQUID such as water, or a gas such as air.
Explanation:
Please help asap
Which choice best explains how you could use the information about the falling pine cones to answer Question 1.
A. If both pine cones are falling at the same speed, the pine cone that weighs less will have more kinetic energy.
B. If both pine cones are falling at the same speed, the pine cone that weighs more will have more kinetic energy.
C. If both pine cones weigh the same, the pine cone that falls faster will have more kinetic energy.
D. If both pine cones weigh the same, the pine cone that falls slower will have more kinetic energy.
Answer:
A
Explanation:
the object's mass determines the speed of the object and its kinetic energy
The general consensus is that our policymakers do not know what they are doing and are managing our economy ineffectively
Answer:
True.
This is because, from the information provided so far, it could be concluded that, the policy makers don't have any single idea of what they are doing regarding to the economy.
This could be seen in the series of poor performance of the economic indicators as shown which has lead to poor economic growth in our country.
Explanation:
Please answer this question sqdancefan
Answer:
(D) 4
Explanation:
The percentage error in each of the contributors to the calculation is 1%. The maximum error in the calculation is approximately the sum of the errors of each contributor, multiplied by the number of times it is a factor in the calculation.
density = mass/volume
density = mass/(π(radius^2)(length))
So, mass and length are each a factor once, and radius is a factor twice. Then the total percentage error is approximately 1% +1% +2×1% = 4%.
_____
If you look at the maximum and minimum density, you find they are ...
{0.0611718, 0.0662668} g/(mm²·cm)
The ratio of the maximum value to the mean of these values is about 1.03998. So, the maximum is 3.998% higher than the "nominal" density.
The error is about 4%.
_____
Additional comment
If you work through the details of the math, you will see that the above-described sum of error percentages is just an approximation. If you need a more exact error estimate, it is best to work with the ranges of the numbers involved, and/or their distributions.
Using numbers with uniformly distributed errors will give different results than with normally distributed errors. When such distributions are involved, you need to carefully define what you mean by a maximum error. (By definition, normal distributions extend to infinity in both directions.) While the central limit theorem tends to apply, the actual shape of the error distribution may not be precisely normal.
Answer:
D. 4Explanation:
#CARRYONLEARNING
justoko2
6) A car of mass 1000kg moving with a velocity of 40m/s collides with a tree and comes to stop in 5s. What will be the force exerted by the car on the tree?
Answer:
Refer to the attachment!~
a car starts from rest & acquire a velocity of 54km/h in 2 sec. Find-
a) the acceleration
b) distance traveled by car assume motion of car is uniform
c) if the mass of the car is 1000kg. what is the force acting on it?
Pls help me. I'm bad in this subject. kinda need it by today
Answer:
a. Acceleration, a = 7.5 m/s
b. Distance, S = 15 meters
c. Force = 7500 Newton
Explanation:
Given the following data;
Mass = 1000 kg
Initial velocity = 0 m/s (since it's starting from rest).
Final velocity = 54 km/h
Time = 2 secs
Conversion:
54 km/h to m/s = 54*1000/3600 = 15 m/s
a. To find the following acceleration;
Mathematically, acceleration is given by the equation;
[tex]Acceleration (a) = \frac{initial speed - final speed}{time}[/tex]
Substituting into the formula, we have;
[tex] Acceleration = \frac{15 - 0}{2}[/tex]
[tex] Acceleration = \frac{15}{2}[/tex]
Acceleration, a = 7.5 m/s
b. To find the distance, we would use the second equation of motion.
[tex] S = ut + \frac {1}{2}at^{2}[/tex]
Where;
S represents the displacement or height measured in meters. u represents the initial velocity measured in meters per seconds. t represents the time measured in seconds. a represents acceleration measured in meters per seconds square.Substituting into the equation, we have;
[tex] S = 0*2 + \frac {1}{2}*(7.5)*2^{2}[/tex]
[tex] S = 0 + 3.75*4[/tex]
[tex] S = 15 [/tex]
Distance, S = 15 meters
c. To find the force, we would use the following formula;
[tex] Force = mass * acceleration [/tex]
[tex] Force = 1000 * 7.5 [/tex]
Force = 7500 Newton
calculate the voltage applied to 2.00
Answer:
Here is your answer
Explanation:
1.55 V is the answer
hope u like it
An effort of 20N is applied to lift a load.If the load arm and effort arm are 15cm and 60cm respectively,calculate the load.
Answer:
Load = 80 Newton
Explanation:
Given the following data:
Effort = 20 N
Load arm = 15 cm
Effort arm = 60 cm
Conversion:
100 cm = 1 meters
15 cm = 15/100 = 0.15 meters
60 cm = 60/100 = 0.6 meters
To calculate the load, we would use the expression;
Effort * effort arm = load * load arm
Substituting into the expression, we have;
20 * 0.6 = load * 0.15
12 = load * 0.15
Load = 12/0.15
Load = 80 Newton
Warda is driving her car down the street. She has a teddy bear sitting on the back seat. A dog runs in front of Warda's car, so she quickly applies the brakes. The force of the brakes causes the car to stop, but the teddy bear continues to move forward until it hits the car's dashboard.
The teddy bear did not stop at the same time as the car because
Answer:
The teddy bear did not stop at the same time as the car because of inertia.
Explanation:
The teddy bear did not stop at the same time as the car because of inertia.
Inertia is a resistance of an object to change its state of motion so if an object is moving it will continue the movement until a force act on it, and vice-versa if an object is at rest it will continue in that state until a force act on it.
Hence, when the teddy bear was in the back seat and the car suddenly stops, the teddy kept moving forward because that was the direction of motion of the car (the teddy bear was moving forward with the car). The force of the brakes acts on the car but not on the teddy bear (not directly), that is why this force does not change the state of motion of the teddy bear.
Therefore, the teddy bear did not stop at the same time as the car because of inertia.
I hope it helps you!
Which of the following describes plastic? HELP
A. A material that as a low resistivity and prevents charges from moving freely
B A material that has a high resistivity and allows charges to move freely
C A material that has a low resistivity and allows charges to move freely
B A material that has a high resistivity and prevents charges from moving freely
Answer:
D
Explanation:
A material that has a high resistivity and prevents charges from moving freely... it is part of insulators...
Plastic is a material that has a high resistivity and prevents charges from moving freely. Option D is correct.
What is plastic?Plastic is described as a material that comprises an organic compound with a significant molecular weight as an important element.
Insulators are often defined as materials that do not allow electricity to flow through them.
Insulators are also referred to as poor electrical conductors. Insulators include materials such as paper, glass, rubber, and plastic.
Plastic is a material that has a high resistivity and prevents charges from moving freely.
Hence option D is correct.
To learn more about the plastic refer to the link;
https://brainly.com/question/23509463
What form of energy is needed to make photosynthesis happen?
A. Proton energy
B. Chemical energ
C. Electron energy
D. Solar energy
Answer:
Photosynthesis converts solar energy into chemical energy.
your answer is solar energy
hope it helps
what is meant by fundamental unit? write any two difference between mass and weight.
Answer:
Fundamental unit is any unit that is not dependent on other units and other units can be derived from them
Explanation:
Units such as Kilogram, Mass and Time are said to be fundamental units because they are independent.
Differences between Mass and weight;
1. Mass is the measure of the amount of matter in a body while weight is a measure of how the force of gravity acts upon that mass.
2. Mass is a scalar quantity while weight is a vector quantity
Explain the energy transformations that occur when breaking in a hybrid
vehicle.
it occur kinetic energy
when breaking in a hybrid
vehicle.
hope it helps
Answer:
it occur kinetic energy when breaking in a hybrid
vehicle .
hope it is helpful to you ☺️
The isotope used to remove cancer malignancy cell the given options are a. Strontium 89 b. Uranium 238 c. Carbon 14 d. Chlorine 37.......... can anyone tell me the ans plzz
Answer:
B. Uranium 238.
Explanation:
It is radioactive and can be used to treat cancer in the form of radiotherapy
A square wooden raft floats on a lake. The density of the water in the lake is 1000 kg/m². The sides of the raft are 2.0m long and the thickness of the raft is 0.20 m. The mass of the raft is 700 kg. How many barrels, each of mass 100 kg, could be placed on the raft before its surface sinks to the surface of the water?
Answer:
1
Explanation:
V=2*2*0.2=0.8m^3
d=m/v 1000*0.8=800kg
800=700+100(n) (n for barrels)
n=1
This question deals with the concept of buoyancy. This can be solved by calculating the buoyant force.
"1" barrels, each of mass 100 kg, could be placed on the raft before it sinks to the surface water.
First, we need to calculate the buoyant force on the raft due to water. This force is equal to the weight of the volume of water equal to the volume of the raft.
Buoyant Force = (Volume of Raft)(Density of Water)(g)
Buoyant Force = [(2 m)(2 m)(0.2 m)][1000 kg/m³](9.81 m/s²)
Buoyant Force = (0.8 m³)(1000 kg/m³)(9.81 m/s²)
Buoyant Force = 7848 N
For the raft to sink the weight of the raft combined with the weight of barrels must exceed the buoyant force. Now, we will calculate the weight of raft and barrels and equate it with the buoyant force.
[Mass of Raft + (No. of Barrels)(Mass of 1 Barrel)][g] = Buoyant Force
[700 kg + (No. of Barrels)(100 kg)][9.81 m/s²] = 7848 N
(No. of Barrels)(981 N) = 7848 N - 6867 N
[tex]No. of Barrels = \frac{981\ N}{981\ N}[/tex]
No. of Barrels = 1
The attached picture shows the concept of buoyancy.
Learn more about buoyancy here:
https://brainly.com/question/21990136?referrer=searchResults
hey what is magnetic field
Answer:
a region around a magnetic material or a moving electric charge within which the force of magnetism acts.
Explanation:
The definition of a magnetic field is a place in space near a magnet or an electric current where a physical field is created from a moving electric charge that creates a force on another moving electric charge. An example of a magnetic field is the Earth's magnetic field.
What is amu?? How is 1amu=1.606*10*-27?
Answer:
amu is atomic mass unit
All of elements hydrogen is the lightest.
Hydrogen is taken as a basic unit so it happened 1amu
So 1 amu must be hydrogen mass
If I am wrong,Pls tell me the true answer....
Behaviors in deer such as herding and male deer using antlers to compete for females increase the chances of successful reproduction.
True or False
Answer:
True
Explanation:
The reproductive success of any species is the capability to produce their offspring per breeding lifetime or event.
Most of the species have to attract their partners by their physical capability and build up so that the mother can choose her partner in order to breed the best kind of off spring.
In the context, in case of deer, the size of the their antlers as well as behavior in herding is considered as the best chances for a successful reproduction to compete among the males and find their breeding mate.
Thus the answer is TRUE.
is our body in thermal equilibrium with the environment ?
Answer:
The human body runs at a constant 37 ºC but the air around you at room temperature is about 20-25 ºC which means heat is constantly leaving your body to warm your surroundings and maintain thermal equilibrium. You don't lose much energy doing this however as air heats reasonably quickly
Explanation:
Which one is best for health? A) Boiled Seeds B) roasted seeds c) wet swollen seeds d)Sprouted seeds
Answer:
d.) "Sprouted seeds"Explanation:
Sprouted seeds - are the best for health.
I hope it helps! Please mark my answer answer as bräinliest (if my answer is correct). Thank You!
The realese of magma from the crater is called earthquake
True or False
Answer:
False
Explanation:
I'm not the most sure but it seems reasonable that it's false
Good Luck Bestie :3
Answer:
The answer is false. If you want why. I will desxribe you.
Please answer in your own words and I will mark brainlist, Compare all matters from the view of passing light through them (name 3 types and write if they pass the light or not.)
Answer:
Light passes through the gas
Light passes through the pure water
Light passes through some solids
Explanation:
In gasses, there are many spaces between the molecules. These spaces allow light to pass through them without any interruption.
In pure water, there are some spaces between particles. these particles allow some light rays to pass theough, some to move through the common boundary and reflec5 some of them.
in solids, some allow light to pass through as they are transparent or translucent
2. What is the water pressure at a depth of 24 m in a lake? [Density of water, p = 1 000 kg m- and gravitational acceleration, g = 9.81 ms-²]
Answer:
Pressure = ρgh
pressure (p) is measured in pascals (Pa)
density (ρ) is measured in kilograms per metre cubed (kg/m3)
The fore of gravitational field strength (g) is measured in N/kg or m/s 2
height of column (h) is measured in metres (m)
Answer = 235,200 Pa
Explanation:
Pressure = ρgh
Pressure = 1,000 x 9.8 x 24
Pressure = 235,200 Pa
Q3. (a) The student places 0.5 kg of potato into a pan of water.
During cooking, the temperature of the potato increases from 20 °C to 100°C
The specific heat capacity of the potato is 3400 J/kg °C
80
Calculate the change in thermal energy of the potato. Use the equation:
change in thermal energy = mass * specific heat capacity * temperature change
m = 0.5kg
C = 34001
TA= 20° - 100°
° = 80°C
OʻS x 3400 x 80 - 136000J
136000
Change in thermal energy =
(b) Why is the energy supplied by the cooker greater than that calculated in part (a)?
HELP
explain mass in physics
Answer:
, a fundamental property of all matter. It is, in effect, the resistance that a body of matter offers to a change in its speed or position upon the application of a force. The greater the mass of a body, the smaller the change produced by an applied force.
there is no gain in mechanical advantage in a single fixed pulley but they are used
Answer:
A single fixed pulley is used to lift load by changing the direction of the lifting force. Even though a single fixed pulley has no mechanical gain in that, the effort applied is greater than the load, it is preferred in use since you do not have to pull or push the pulley up and down.
Explanation:
The answer itself speaks
The relative density ofbrass is 8.4. Which of
the following is the BEST statement that can
be made?
(A)
(B)
(C)
Brass is heavier than water.
Water is heavier than brass.
100 cm' of brass is heavier than 100
cm' of water.
100 cm'ofwateris heavier than 100
cm of brass.
(D)
A.brass is heavier than water.
A brick is lying on a table in a state of static equilibrium. If the mass of the brick is 7.52 kilograms, what is the normal force exerted by the table on the brick?
Answer:
-mg = -7.52*9.8 = - 73.696N
Answer:
See image
Explanation:
Plato