Answer:
In collisions between two isolated objects Newton's third law implies that momentum is always conserved. In collisions between two isolated objects momentum is always conserved. Kinetic energy is only conserved in elastic collisions.
Explanation:
An 80kg sled rider starts sledding down a 100m hill from rest. If her final velocity is 15m/s, what is he acceleration down the hill? What is the force needed for that kind of acceleration
Given :
An 80kg sled rider starts sledding down a 100m hill from rest. If her final velocity is 15m/s.
To Find :
The acceleration down the hill.
The force needed for that kind of acceleration.
Solution :
By equation of motion :
[tex]v^2 -u^2 = 2as\\\\a = \dfrac{v^2-u^2}{2s}\\\\a = \dfrac{15^2 -0^2}{2\times 100}\\\\a = 1.125\ m/s^2[/tex]
Force required is, F = ma
F = 80×1.125 N
F = 90 N
Hence, this is the required solution.
Think about a typical school day. In the space provided below, describe how each of the different forms of energy we have learned about (chemical, electrical, heat, kinetic, potential, and solar) are used during a typical school day and how each form of energy is transformed into another.
Answer:
During a typical school day all forms of eneergy is being utilised and also transfer of energy takes place from one form to another.
Explanation:
Chemical energy- A bunsen burner burning a beaker filled with water.
Heat energy- The water in the beaker absorbing the heat from the burner.
Electrical energy- Running Fans and lights in a classroom by switches.
Solar energy- Solar energy harnessed by solar panels to run the fans and lights by converting it into electrical energy.
Potential energy- A ball being held by a student at a certain height possesses energy due to gravity.
Kinetic energy- The same ball being left by the boy from a certain height produces kinetic energy
Answer:
Explanation:
Chemical energy- A bunsen burner burning a beaker filled with water.
Heat energy- The water in the beaker absorbing the heat from the burner.
Electrical energy- Running Fans and lights in a classroom by switches.
Solar energy- Solar energy harnessed by solar panels to run the fans and lights by converting it into electrical energy.
Potential energy- A ball being held by a student at a certain height possesses energy due to gravity.
Kinetic energy- The same ball being left by the boy from a certain height produces kinetic energy
Which of the following is the most important factor in determining an element’s place in the periodic table?
A. Number of protons
B. Number of neutrons
C. Atomic Charge
D. Atomic Density
Un corp de masa m=5 kg se afla pe o suprafata orizontala pe care se poate deplasa cu frecare (µ = 0,02). Calculati forta de frecare.
Răspuns:
0,98 N
Explicaţie:
Dat fiind:
µ = Coeficientul de frecare = 0,02
Masa (m) = 5 kg
Folosind relația:
Forța de frecare (F) = µ * N
N = reacție normală = masă * accelerație datorată gravitației
Prin urmare,
F = u * m * g
g = 9,8 m / s²
F = 0,02 * 5 kg * 9,8 m / s²
F = 0,98 kgm / s²
F = 0,98N
When a piece of iron or mass 78 gm is put in a graduated cylinder containing 100 cm cube of water the reading of the cylinder become 110cm cube
Calculate the density of iron.
Answer:
Ro = 7.8 [g/cm³]
Explanation:
According to the principle of Archimedes, the volume of a body immersed in a liquid is equal to the volume displaced by water. That is, in this problem The displacement volume is equal to the new volume minus the original volume.
[tex]V_{n}=110[cm^{3} ]\\V_{o}=100[cm^{3} ]\\V_{d}=110-100 = 10 [cm^{3} ][/tex]
We now know that density is defined as the relationship between mass and volume.
[tex]Ro = m/V_{d}[/tex]
where:
Ro = density [g/cm³]
m = mass = 78 [g]
Vd = displacement volume [cm³]
[tex]Ro = 78/10\\Ro = 7.8 [g/cm^{3} ][/tex]
If you push an 5 N object 2 m and then push a 10 N object 2 m. Which is TRUE?
You do the same amount of work.
You do more work when you move the 10 N object.
You are more powerful when you move the 5 N object
O You use the same amount of force.
Answer:
Explanation:
You don't do the same amount of work. The work formula is F*d = W
W = work
F = force
d = the distance moved.
So you do more work when you move the 10N object because the Force (F) has doubled.
need ASAP WILL MARK BRANLIEST
Answer:
pls refer to attachments
A balloon drifts 14 km at an angle of 30º to the ground. What is the vertical component of the balloon
Sin is the vertical component. So multiply sin 30 and 14. BOOM! You got the answer.
[tex] \sin(30) \times 14 \: = 7[/tex]
. A motorist is speeding along at 33m/s when he sees a squirrel on the road 200 meters in
front of him. He tries to stop, but it takes 12 seconds for his car to stop
(a) What is the acceleration of the car? (assume acceleration was constant)
(b) Does the squirrel survive?
(c) How fast was the car moving at 100 meters?
Hello!
a)
Use the kinematic equation to solve for the acceleration:
[tex]v_{f} = v_{i} + at[/tex]
In this instance, the final velocity is 0 because he comes to a stop. We can solve for the acceleration by plugging in the given values:
0 = 33 + (12)a
0 = 33 + 12a
-33 = 12a
-33 / 12 = a --> a = -2.75 m/s²
b) Find the amount of distance necessary to stop. Use the formula:
[tex]v_{f} ^{2} = v_{i} ^{2} + 2ad[/tex]
Plug in the values:
0² = 33² + 2(-2.75 · d)
0 = 1089 - 5.5d
-1089 = -5.5d
d = 198 meters. Therefore, the squirrel would survive.
c)
Find the velocity at 100 meters by using the same formula as before:
[tex]v_{f} ^{2} = v_{i} ^{2} + 2ad[/tex]
However, in this instance, we are solving for the final velocity. Plug in the given points to solve:
vf² = 33² + 2(-2.75 · 100)
vf² = 1089 + (-550)
vf² = 539
vf = √539
vf ≈ 23.22 m/s.
A football tube in the form of a sphere is inflated so that it radius increases in the ratio 4:3 . Find the ratio in which the volume is increased.
Answer:
The volume is increased in a ratio of 64/27
Explanation:
The Volume of a Sphere
The volume of a sphere of radius r is given by:
[tex]\displaystyle V=\frac{4}{3}\cdot \pi\cdot r^3[/tex]
If the radius was changed to r', the new volume would be:
[tex]\displaystyle V'=\frac{4}{3}\cdot \pi\cdot r'^3[/tex]
Dividing the latter equation by the first one:
[tex]\displaystyle \frac{V'}{V}=\frac{\frac{4}{3}\cdot \pi\cdot r'^3}{\frac{4}{3}\cdot \pi\cdot r^3}[/tex]
Simplifying:
[tex]\displaystyle \frac{V'}{V}=\frac{r'^3}{r^3}[/tex]
Or, equivalently:
[tex]\displaystyle \frac{V'}{V}=\left(\frac{r'}{r}\right)^3[/tex]
Since r':r = 4:3, thus:
[tex]\displaystyle \frac{V'}{V}=\left(\frac{4}{3}\right)^3[/tex]
[tex]\displaystyle \frac{V'}{V}=\frac{4^3}{3^3}[/tex]
[tex]\displaystyle \frac{V'}{V}=\frac{64}{27}[/tex]
The volume is increased in a ratio of 64/27
A roller coaster car has 600,00 J of Kinetic energy as it approaches the station to stop. The roller coaster comes to a complete stop. How much work did the brakes do in stopping the car?
Answer:
Work Done by the Brakes = - 60000 J
Negative sign indicates the opposite direction of force and displacement.
Explanation:
Assuming that frictional effects are negligible, we can say that all the work done by the brakes is used to stop the car. We can apply law of conservation of energy to this situation as follows:
Work Done by the Brakes = Change in Kinetic Energy
Work Done by the Brakes = Final Kinetic Energy - Initial Kinetic Energy
Final Kinetic Energy of the roller coaster will be 0. Because, the roller coaster will stop finally and its velocity will become zero.
Work Done by the Brakes = 0 J - 60000 J
Work Done by the Brakes = - 60000 J
Negative sign indicates the opposite direction of force and displacement.
A cyclist travels 100 kilometers in 4 hours. What is the cyclist speed?
Answer:
100x4=400 kilometers
Explanation:
: )
Answer:
100÷4=25
Explanation:
you would devide
how did Albert Einstein come up with 3 = mc square pls help
Answer: He came up with this by using theories like the photoelectric effect, the second offered experimental proof of the existence of atoms, and the third introduced the theory of special relativity.
Explanation: He was explaing the realationship between energy and mass.
Me: Hope this helps!!! May I have brainlist!?
Help!!
Which is the most common source of ocean oil pollution?
A.oil spills
B.street runoff
C.offshore drilling
D.ship repairs
Answer:
Oil Spills.
Explanation:
Answer:
C
Explanation:
Solve the following question and select the final answer:
The momentum of a bullet of mass 20kg fired from a gun is 10 kg m/s. The kinetic energy of this bullet in Kj will be:
a)5
b)1.5
c)2.5
d)25
Answer: 2.5
Explanation:
The mass of bullet = 20kg
The momentum of the bullet = 10kg m/s
The kinetic energy of this bullet in Kj will be calculated as:
= p² / 2m
= 10² /(2 × 20)
= (10 × 10) /(2 × 20)
= 100/40
= 2.5
Therefore, the correct option is C.
Anyone....................
Answer:
h₁ = 18 [cm]
Explanation:
This problem can be solved by applying the principles of the static pressure of a liquid column. The key to the solution is to know that the pressure on the horizontal line should be equal for both liquids, this must be met regardless of their density.
[tex]P_{2}=P_{1}\\[/tex]
where:
P₂ = Pressure exerted by the liquid 2 in the given point L₂
P₁ = Pressure exerted by the liquid 2 in the given point L₁
Now we can calculate the pressure in each point using the following expression:
[tex]P_{1}=Ro_{1}*g*h_{1}\\P_{2}=Ro_{2}*g*h_{2}[/tex]
Where:
Ro₁ = density of the liquid 1 = 0.8 [g/cm³]
Ro₂ = density of the liquid 2 = 1.8 [g/cm³]
g = gravity acceleration = 9.81 [m/s²]
h₁ = column of the liquid 1 [m]
h₂ = column of the liquid 2, = 8 [cm] = 0.08 [m]
But first we must convert the units from grams per cubic centimeter to kilograms per cubic meter.
[tex]0.8[\frac{g}{cm^{3}}]*[\frac{1kg}{1000g} ]*[\frac{100^{3}cm^{3} }{1m^{3} } ]=800[kg/m^{3} ]\\1.8[\frac{g}{cm^{3}}]*[\frac{1kg}{1000g} ]*[\frac{100^{3}cm^{3} }{1m^{3} } ]=1800[kg/m^{3} ][/tex]
Now replacing in the first equation:
[tex]800*9.81*h_{1}=1800*9.81*0.08\\h_{1}=\frac{1800}{800} *0.08\\h_{1}=0.18 [m] = 18 [cm][/tex]
Answer:
[tex]h_1 = 18 \: cm[/tex]
Explanation:
See image for explanation
I hope my working is correct.
what is measurnment
Answer:
measurement is the comparison of unknown physical physical quantity with know standard quantity of the same kind .
What is the KE of a 6 kg mass at 4 m/s?
The KE of a 6 kg mass at 4 m/s will be 48 J. The kinetic energy is obtained, found as the product of mass and the square of the velocity.
What is Kinetic energy?The energy possessed by the body by the virtue of motion is known as the Kinetic energy. It is found as the product of mass and the square of the velocity.
The given data in the problem is;
The mass is, m=6 kg
The velocity is,v= 4 m/s
The kinetic energy is found as;
[tex]\rm KE = \frac{1}{2}mv^2 \\\\\ \rm KE = \frac{1}{2}6 (4) ^2\\\\\ KE= 48 \ J[/tex]
Hence, the KE of a 6 kg mass at 4 m/s will be 48 J.
To learn more about the kinetic energy, refer to the link;
https://brainly.com/question/12669551
#SPJ2
Why's earths magnetosphere important ?
Answer:
The Earth's magnetic field protects life on Earth, shielding it from damaging radiation and moderating our climate. So the idea that it could completely flip around, or collapse altogether, should cause us
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what is newton's third law of motion
Newton's Third Law of Motion states "To every action, there is an equal and opposite reaction; action and reaction forces act on different bodies".
the rubber covering over a wire acts as a / an ?
Answer:
Most electrical wire is covered in a rubber or plastic coating called insulation. The purpose of insulation covering the metal part of an electrical wire is to prevent accidental contact with other conductors of electricity, which might result in an unintentional electric current through those other conductors.
Explanation:
A student presses her palm by her thumb with a force of 75 N . What would be the pressure under her thumb having contact area is 1.5 cm2
Answer:
Pressure = 50 N/cm²
Explanation:
Given:
Force = 75 N
Area = 1.5 cm²
Find:
Pressure
Computation:
Pressure = Force / Area
Pressure = 75 / 1.5
Pressure = 50 N/cm²
Pls help me with my work
Which best describes reflection and refraction?
In both reflection and refraction, rays pass through a boundary.
In both reflection and refraction, rays bounce off a boundary.
In reflection, rays bounce off a boundary, and in refraction, rays pass through a boundary.
In refraction, rays bounce off a boundary, and in reflection, rays pass through a boundary.
Answer:
The correct answer is the third option
Explanation:
To reflect means to bounce off. When an incoming ray (called incident ray) gets to a boundary and bounces off the boundary, that is referred to as reflection. However, when an incident ray passes through the boundary and it causes a change in the direction of propagation of the wave, that is referred to as refraction. Thus, the correct option, as explained above, is; In reflection, rays bounce off a boundary, and in refraction, rays pass through a boundary.
Answer:
c
Explanation:
on edge 2020
What does dalton theory have in common with democritus
Answer:
Democritus and Dalton has similar ideas about the atom, but Democritus based his theory more on reason than science. ... His ideas were similar to those of Democrites in that he believed that atoms were indivisible and that atoms of one substance are all alike but are different from atoms of another substance.
Explanation:
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Answer:
Democritus and Dalton has similar ideas about the atom, but Democritus based his theory more on reason than science. ... His ideas were similar to those of Democrites in that he believed that atoms were indivisible and that atoms of one substance are all alike but are different from atoms of another substance.
Explanation:
what type of process occurs at constant pressure
Answer:
isobaric process
Explanation:
An isobaric process occurs at constant pressure. Since the pressure is constant, the force exerted is constant and the work done is given as PΔV.
Answer:
well for me I think it's
Explanation:
Charles law in gas laws
What does the Nucleolus do?
A) Makes ribosomes
B) Controls the nucleus
C) Controls the cell
D) Creates cytoplasm and lipids
Answer:
C
Explanation:
Answer:
A) Makes ribosomes
Explanation:
The nucleolus assembles the ribosomes of a cell, which are then sent to the cytoplasm to be used.
Four quartz samples of equal size and shape were placed in a stream. Which of the four quartz samples below has most likely been transported farthest in the stream?
I've attached the complete question.
Answer:
Option D
Explanation:
From the quartz images attached, we can see they now have different shapes, level of roughness and irregularity. However, the one that will have transported farthest will be option D which is the one that looks circular and has undergone the most abrasion from its body surface and size so far . This is because abrasion is a type of weathering were rocks and sediments wear out their surfaces by grinding out against each other.
The only option that looks to have undergone the most abrasion which means has transported the farthest is the sample in option D
SAT QUESTION // A capacitor is connected to a variable power supply with potential V. Determine the effect on the charge stored on the capacitor if the potential of the power supply is cut in half.
Answer:
decrease by a factor of 2
Land plants are adapted to survive on land through stomata to regulate water regulation, specialized cells, structures that collect sunlight, and water!
Answer:
stomata to regulate water
specialized cells
Explanation:
Land plants are able to successfully adapt to staying on land through the use of stomata to regulate water loss and through the development of specialized cells that give support to grow erect.
Water regulation is important for the survival of plants on land, otherwise, they may face desiccation as a result of the heat from the sun. The stomata is a structure found on the leaves of land plants that open and close to regulate the amount of water lost to the environment through evapotranspiration. When there is adequate water and the plant can afford to lose some water, the stomata open, otherwise, the stomata close.
Support is also important for land plant's survival and the development of specialized cells in the form of sclerenchyma cells take care of this. The fibers and sclerids are two types of sclerenchyma cells that primarily function to support the land plants.