Explanation:
Natural selection is the process through which populations of living organisms adapt and change. Individuals in a population are naturally variable, meaning that they are all different in some ways. This variation means that some individuals have traits better suited to the environment than others
A car accelerates from rest at a constant acceleration of 25.0 m/s^2. At some point, it then turns off its engine, letting the car decelerate slowly from the force of friction at a constant deceleration of 3 m/s^2 until it is at rest again. The total speed the car moves in this time is 200 meters. What is the minimum time needed for the car to move 200 meters given that it both starts and ends at rest?
Answer:
t = 9.14 s
Explanation:
We first analyze the accelerating motion by applying first equation of motion:
Vf₁ = Vi₁ + a₁t₁
where,
Vf₁ = Final Speed of Car before turning off engine
Vi₁ = Initial Speed of Car = 0 m/s
a₁ = acceleration of car = 25 m/s²
t₁ = time taken in accelerating motion
Therefore,
Vf₁ = 25t₁ ---------- equation (1)
Now, we apply second equation of motion:
s₁ = Vi₁ t₁ + (1/2)a₁t₁²
where,
s₁ = distance covered during accelerating motion
Therefore,
s₁ = (0)t₁ + (1/2)(25)t₁²
s₁ = 12.5 t₁² ----------- equation (2)
Now, we analyze the decelerating motion by applying first equation of motion:
Vf₂ = Vi₂ + a₂t₂
where,
Vf₂ = Final Speed of Car = 0 m/s
Vi₂ = Initial Speed of Car after turning off engine
a₂ = deceleration of car = - 3 m/s²
t₂ = time taken in decelerating motion
Therefore,
Vi₂ = 3t₂ ---------- equation (3)
Now, we apply second equation of motion:
s₂ = Vi₂ t₂ + (1/2)a₂t₂²
where,
s₂ = distance covered during decelerating motion
Therefore,
s₂ = (Vi₂)t₂ + (1/2)(-3)t₂²
s₂ = Vi₂ t₂ - 1.5 t₂²
using equation (3):
s₂ = 3 t₂² - 1.5 t₂²
s₂ = 1.5 t₂² ------------ equation (4)
Now, we know that the Final Velocity of accelerating motion (Vf₁) is equal to the initial velocity of decelerating motion (Vi₂):
Vf₁ = Vi₂
using equation (1) and equation (3):
25 t₁ = 3 t₂
t₁ = 0.12 t₂ ------------ equation (5)
Also, we know that sum of the distances is 200 m:
s₁ + s₂ = 200
using equation (2) and equation (4):
12.5 t₁² + 1.5 t₂² = 200
using equation (5):
12.5 (0.12 t₂²) + 1.5 t₂² = 200
3 t₂² = 200
t₂² = 200/3
t₂ = 8.16 s
substitute this in equation (5):
t₁ = 0.12(8.16 s)
t₁ = 0.97 s
Hence, the minimum time required for this motion is:
t = t₁ + t₂ = 0.97 s + 8.16 s
t = 9.14 s
In which of the following situations would there be initial energy in the system?
An apple sits motionless on the ground near a tree
A spring is compressed and held at compression by a person before releasing it
A bowstring is neither pulled nor stretched on a bow
An object rests at a velocity of 0 on a flat surface at ground level
Answer:
A spring is compressed and held at compression by a person before releasing it
Explanation:
All the other answers are showing things that are at rest and have no energy starting nor going through them. This answer show how the energy is starting and being released.
Can someone help me in this please any one good in science.
Let's calculate the equivalent resistances on both circuits.
On Diagram A we have a series connection of the resistors. The equivalent resistance will be the sum of all resistances:
[tex]R_{eq}=1+1+1\\\\\boxed{R_{eq}=3\Omega}[/tex]
On diagram B we have a parallel connection of the resistors. The reciprocal of the equivalent resistance will be the sum of the reciprocals of all the resistances:
[tex]\frac{1}{R_{eq}} = \frac{1}{1} +\frac{1}{1} +\frac{1}{1} \\\frac{1}{R_{eq}}=3\\\\\boxed{R_{eq}=\frac{1}{3}}[/tex]
Therefore, the larger resistance occurs on diagram A.
For the current, recall
[tex]V=IR[/tex]
Where [tex]I[/tex] stands for current [tex]R[/tex] is the resistance and [tex]V[/tex] is the voltage. Rearranging the equation we have
[tex]I = \frac{V}{R}[/tex]
We can see that the larger the resistance, the smaller the current gets. So the larger current must happen in the diagram with smaller resistance. Therefore, the larger current occurs on diagram B.
Glad to help, wish you great studies ;)
Mark brainliest if you deem the answer worthy
PLEASE HELP ME IM TIMED
Answer:
the answer is the core
Explanation:
the core is composed of iron and nickel
One of the major differences between our common Physics models of energy change and realistic models of them is
In the Physics models, the acceleration due to gravity is rounded to a non-exact but easier to use number
In the Physics models, the velocities are only calculated at set intervals of time, instead of continuously
In the Physics models, the objects are assumed to have simplified shapes in order to make motion by acceleration easier to calculate
In the Physics models, we do not take into account the energy change by the friction of moving components
Answer: In the Physics models, we do not take into account the energy change by the friction of moving components
Explanation:
Starting from rest, a spinning disk accelerates constantly to a final rotational speed, ω , in a period of time, Δ Δ t. What expression best represents the revolutions the disk has turned through? A) ω Δ Δ t /2 π B) Δ4 ω Δ t 4 π C)Δ22 ω Δ t 2 2 D) Δ ω Δ t E) 2Δ 2 π ω Δ t
Answer:
the correct one is B, θ = [tex]\frac{1}{4\pi }[/tex] w t [rev]
Explanation:
This is a rotational kinematics exercise
w = w₀ + α t
w² = w₀² + 2 α θ
indicate that part of rest whereby the initial angular velocity is zero
w = α t -> α = w/t
w² = 2 α θ
we substitute
w² = 2 (w / t) θ
w = 2 θ / t
θ = w t / 2
This angle is given in radians, let's reduce to revolutions = 2π rad = 1 rev
θ = w t / 2 rad (1 rev / 2π rad)
θ = [tex]\frac{1}{4\pi }[/tex] w t [rev]
when checking the answers, the correct one is B, even though he has some mistakes in his writing
A 125,000 kg locomotive is traveling south at 1.0 m/s through a switching yard. A connected set of parked gondola cars weighing 1,750,000 kg are directly ahead. Determine the speed and direction of the completed train after the locomotive has been coupled to the cars.
Answer:
The speed of the completed train is 0.0[tex]\bar 6[/tex] m/s
The direction of the completed train is South
Explanation:
The given parameters are;
The mass of the locomotive, m₁ = 125,000 kg
The initial speed of the locomotive, v₁ = 1.0 m/s
The mass of the gondola cars, m₂ = 1,750,000 kg
The initial sped of the gondola cars, v₂ = 0
Let v₃ represents the speed of the completed train. From the principle of conservation of linear momentum, we have;
m₁·v₁ + m₂·v₂ = (m₁ + m₂)×v₃
Substituting the known values, gives;
125,000 × 1.0 + 1,750,000 × 0 = (125,000 + 1,750,000) × v₃
∴ v₃ = (125,000 × 1.0 + 1,750,000 × 0)/(125,000 + 1,750,000) = 1/15 = 0.0[tex]\bar 6[/tex]
v₃ = 0.0[tex]\bar 6[/tex] m/s
The speed of the completed train = 0.0[tex]\bar 6[/tex] m/s
The direction of the completed train = The direction of the locomotive = South.
How do we obtain data about the properties of exoplanets and objects in our solar system?
Answer:
Doppler effect to analyze the motion and properties of the star and planet.
Explanation:
The radial velocity method invovles watching the spectral lines of a star as a planet orbits around the star. Because of the planets gravitational pull on the star, will wobble. This causes Doppler shifts in the spectral lines, allowing astronomers to infer the presence of the planets.
Question 5 (1 point)
A child kicks a ball horizontally with a speed of 4.8 m/s off a deck 3.5 m off the
ground. How far, in meters, from the deck does the ball land on the ground?
Answer:
The horizontal distance the ball travels is approximately 4.055 meters
Explanation:
The given parameters are;
The height from which the child kicks the ball = 3.5 m
The horizontal speed of the ball = 4.8 m/s
Therefore, we have;
The time it takes the ball to hit the ground is given by the relation;
h = u·t + 1/2·g·t²
Where;
u = The initial vertical velocity of the ball = 0 m/s
t = The time it takes the ball to hit the ground
g = The acceleration due to gravity = 9.81 m/s²
h = The height of the ball = 3.5 m
3.5 = 0 × t + 1/2 × 9.81 × t²
3.5 = 1/2 × 9.81 × t²
∴ t² = 3.5/(1/2 × 9.81)
∴ t = √(3.5/(1/2 × 9.81) = 0.8447 s
t ≈ 0.8447 s
The time the ball takes in flight = t ≈ 0.8447 s
Therefore;
The horizontal distance the ball travels = The horizontal velocity × The time of flight
∴ The horizontal distance the ball travels = 4.8 × 0.8447 ≈ 4.055
The horizontal distance the ball travels ≈ 4.055 meters.
Which point has the most Potential energy? [Select]
Which point has the most Kinetic energy? [ Select ]
Answer:
Most potential energy: A
Most kinetic energy: D
Explanation:
Kinetic Energy is the type of energy an object has due to its state of motion. It's proportional to the square of the speed.
The equation for the kinetic energy is:
[tex]\displaystyle K=\frac{1}{2}mv^2[/tex]
Where:
m = mass of the object
v = speed at which the object moves
The gravitational potential energy is the energy stored in an object because of its height h in a gravitational field.
It can be calculated with the equation:
U=m.g.h
The point where the object has the most potential energy is that where it has more height. It corresponds to point A.
When the object is at zero height, all of its potential energy was transformed to kinetic, thus the point where the kinetic energy is D.
Most potential energy: A
Most kinetic energy: D
Answer:
potentail enegry at point a and kinetic enegy at point c
Explanation:
i did this i fourth grade please mark brainlist
1. A large ocean liner floating in the sea has a volume of
375 000 m² and displaces 50 000 m² of sea water. Determine the
density and mass of the ship. Explain why, despite being made
of metal, the ship is able to float.
Answer:
Density of the ship :133.33 kg/m³
Mass of the ship :50,000,000 kg
Ships are able to float on water because they displace a volume that equals their own weight
Explanation:
The formula for density is ;
Density = Mass/Volume
But the mass of displaced fluid is give by the formula;
m=ρV where ρ is density of the fluid and V is volume of water displaced
Volume of liner= 375000 m³
Volume displaced = 50000 m³
The volume of the water displaced is equal to mass of the liner
I m³ = 1000 kg
50000 m³ = 50000*1000 =50,000,000 kg
50,000,000 kg ----------mass of the ship
So if ;
m= 50,000,000 kg
v= 375000 m³
ρ = m/V
ρ = 50,000,000/375000
ρ = 50,000,000/375000
ρ =133.33 kg/m³
Ships are able to float on water because they displace a volume that equals their own weight. Additionally, the air contained in the spaces of the ship inside is much less dense than density of water aiding in the floating process.
does an object in motion stay in motion
How much Tension force is required to pull a 1500 kg car (it is being towed) forward with an acceleration of 3 m/s^2 if the friction force on the towed car's tires is pulling backward with a force of 2500 N?
If the pull is done horizontally, then the net force on the car is
∑ F = T - f = (1500 kg) (3 m/s²)
where T is the magnitude of the tension in the towing cable, and f is the friction which points in the opposite direction. Then
T = f + (1500 kg) (3 m/s²)
T = 2500 N + 4500 N
T = 7000 N
A 2450 kg stunt airplane accelerates from 120 m/s to 162 m/s in 2.10s. If the airplane is putting out an average force of 5.8810x10^4 N during this time, what is the average friction force exerted on the airplane by the air?
Given :
A 2450 kg stunt airplane accelerates from 120 m/s to 162 m/s in 2.10 s.
If the airplane is putting out an average force of [tex]5.8810\times 10^4 \ N[/tex].
To Find :
The average friction force exerted on the airplane by the air.
Solution :
Acceleration is given by :
[tex]a = \dfrac{162-120}{2.10}\ m/s^2\\\\a = 20 \ m/s^2[/tex]
Now, force equation is given by :
[tex]F - F_{friction} = ma\\\\F_{friction} = F-ma\\\\F_{friction} = 58810 - (2450\times 20 )\\\\F_{friction} = 9810\ N[/tex]
Therefore, frictional force exerted in the airplane by the air is 9810 N.
4. A Ferrari travels 350km in 2 hours. What was it's
s speed?
3. A cart with mass of 30 kg is traveling with a velocity of 4.0 m/s. The
cart then gains speed, achieving a new velocity of 10 m/s after 4
seconds. Calculate the magnitude of the net force acting on the cart.
Answer:
39 m/s
Explanation:
Answer:
39 m/s
Explanation:
As we know, the moon is a satellite of our earth, what is the
theoretical period of the moon? The average radius of the
moon's orbit is 3.84 108 m and the mass of the earth is 5.97 x
1024 kg (in hours, G = 6.67 x 10-9 N (m/kg) 3).
Answer:c
Explanation:c
This question involves the concepts of the time period, orbital radius, and gravitational constant.
The theoretical period of the moon is "658 hr".
The theoretical time period of the moon around the earth can be found using the following formula:
[tex]\frac{T^2}{R^3}=\frac{4\pi^2}{GM}[/tex]
where,
T = Time Period of Moon = ?
R = Orbital Radius = 3.84 x 10⁸ m
G = Gravitational Constant = 6.67 x 10⁻¹¹ N.m²/kg²
M = Mass of Earth = 5.97 x 10²⁴ kg
Therefore,
[tex]\frac{T^2}{(3.84\ x\ 10^8\ m)^3}=\frac{4\pi^2}{(6.67\ x\ 10^{-11}\ N.m^2/kg^2)(5.97\ x\ 10^{24}\ kg)}\\\\T^2=(9.91\ x\ 10^{-14}\ s^2/m^3)(56.62\ x\ 10^{24}\ m^3)\\\\T=\sqrt{561.34\ x\ 10^{10}\ s^2}[/tex]
T = 2.37 x 10⁶ s[tex](\frac{1\ h}{3600\ s})[/tex]
T = 658 hr
Learn more about the orbital time period here:
https://brainly.com/question/14494804?referrer=searchResults
The attached picture shows the derivation of the formula for orbital speed.
A river flows due east at 1.50 m/s. A boat crosses the river from the south shore to the north shore by maintaining a constant velocity of 10.0 m/s due north relative to the water. If the river is 325 m wide, how far downstream is the boat when it reaches the north shore?
Answer:
Explanation:
Given that the velocity of the river is 1.50m/s due east.
The velocity of the boat with respect to the river is 10.0 m/s due north .
The width of the river is 325 m.
Note that the velocity of the boat will help in crossing the river.
Hence, speed = distance/time
Speed = 10.0 m/s
Distance = 325 m
Time = ?
10 = 325/time
Time = 325/10
Time = 32.5s
Hence in 32.5s the horizontal distance traveled by boat will be
= 1.50m/s × 32.5s
= 48.75m
The largest acceleration that a human has ever endured occurred when a race car accidentally crashed into a wall. The car was traveling at a speed of 172.8 km/h when it hit the wall. The car came to a complete stop 2.72 ´ 10–2 s later.
a. Calculate the acceleration of the car using the acceleration formula. Express your answer in both m/s2 and in “g’s.” One g is equal to the free-fall acceleration of 9.8 m/s2.
b. Suppose the driver of the car had a mass of 70.0 kg. What was the unbalanced force on his body as the car underwent negative acceleration?
Answer:
(a) The acceleration oF the car is [tex]-1764.7 m/s^2[/tex] or -180.1 g’s.
(b) The magnitude of the force on the driver's body is 123529 Newtons
Explanation:
Given that:
The initial velocity of the car before the impact, u=172.8 km/h
Or, [tex]u =172.8 \times \frac {1000}{3600} m/s= 48m/s[/tex]
As the car came to a complete stop after the collision, so the final velocity of the car, v=0.
The time required to stop the car completely, [tex]t=2.72\times 10^{-2} s[/tex]
(a) Assuming the acceleration is constant, so
Acceleration, [tex]a= (v-u)/t[/tex]
So, [tex]a=\frac {0-48}{2.72\times 10^{-2}}=-1764.7 m/s^2[/tex]
Now, expressing the acceleration in the unit od "g's",
[tex]a=-1764.7\times \frac{g}{g} \\\\\Rightarrow a=-1764.7 \;m/s^2\times \frac{g}{9.8\; m/s^2} \\\\\Rightarrow a=-180.1 g[/tex]
Hence, the acceleration od the car is -1764.7 [tex]m/s^2[/tex] or -180.1 g’s.
(b) Mass of the driver of the car, m=70.0 kg
The acceleration of the body of the driver is the same as the acceleration of the car.
So, the acceleration faced by the driver, [tex]a= -1764.7 m/s^2[/tex]
As forec = mass x acceleration, so
The force on the driver's body = 70 x (-1764.7)= -123529 Newtons.
The negative sign means the force is in the opposite direction of the direction of motion of the car.
Hence, the magnitude of the force on the driver's body is 123529 Newtons
INEGRATED SCIENCE-8th grade science
report cards due dec.18
Please Help ASSSAAAAPPPP! PLEASEEEEEEE
Answer:
I do drink bottled water but not to often, I live about 2.8 miles away from its water source and if i did'nt drink bottled water and I had to found out how my drinking water is treated I would go ask the people that are taking care of the water.
Explanation:
hope this helps
Students are asked to design an experiment about Newton’s 2nd Law. One student decides to roll a marble down a ramp into a pile of sand to measure the force impact.
Which variable should she manipulate to best exemplify the relationship explained by this law?
A.She should use a heavier marble, because the marbles will roll at the same rate of acceleration but more mass will produce a larger impact force.
B.She should increase the slope of the ramp by propping it up to higher height, because a steeper ramp will cause a greater rate of acceleration and a larger impact force.
C.She should use a heavier marble, because a bigger marble will accelerate more quickly down the ramp and cause a greater impact force.
D.She should decrease the slope of the ramp, because a ramp with a smaller slope will allow the ball more time to build up speed and cause a greater impact force.
Answer:
A
Explanation:
Trust me I just took it !
Integrated Science- 8th grade science
Please Help ASAP!
Its almost the end of semester And I need to fix my grade for science so PLEASE help!
its almost report cards time!
Answer:
A. a rigorously tested explanation
Explanation:
B. and D. are out - theories are not opinionated, they are factualC. is out - not all theories are mathematicalA. is the best choiceAnswer:
The answer is option letter B
Could somebody please explain the Coriolis effect? Thank you! (also the subject is physical science but that wasn't an option so I just put physics)
Answer:
The Coriolis Effect makes things appear to move in a curve around our planet, like, for example, a plane. This is also due to the fact that our Earth is round, so nothing really moves in a straight line. It is "an effect whereby a mass moving in a rotating system experiences a force (the Coriolis force ) acting perpendicular to the direction of motion and to the axis of rotation."
Explanation:
A lava lamp is a decorative item found in some homes. The lamp portion contains a waxy substance in a liquid medium. When the lamp is plugged in, a bulb at the base of the lamp slowly heats the waxy substance sitting at the bottom of the liquid. Eventually, the waxy substance will separate into globs that quickly rise to the top of the lamp where the surrounding liquid cools them and causes them to fall back to the bottom. Based on the information provided, a lava lamp could be used to provide an example of which process of thermal energy transfer?
Answer:
Conduction, convection, and radiation
Explanation:
Conduction is the process in which energy is transferred from a hot body to a cooler body. Convection is a process by which heat is transferred as a result of the movement of heated fluid in the form of air or water. Radiation refers to the transmission of energy through a material medium.
Based on the information provided, a lava lamp could be used to provide an example of conduction, convection, and radiation.
what makes up a atom
Answer:
They're typically made up of three main parts: protons, neutrons and electrons. Think of the protons and neutrons as together forming a “sun”, or nucleus, at the centre of the system. The electrons orbit this nucleus, like planets. If atoms are impossibly small, these subatomic particles are even more so.
Explanation:
hope i helped.
Answer:
Atoms consist of a nucleus made of protons and neutrons orbited by electrons. ... We now know that atoms are made up of three particles: protons, neutrons and electrons — which are composed of even smaller particles, such as quarks.
Explanation:
When momentum is conserved it is called _____. (multiple choice)
A.) Conservation of Momentum
B.) The Law of Momentum
C.) The Physics of Momentum
D.) The Rules of Momentum
Answer:
Based off the word "conserved" I would say
A. Conservation of Momentum.
Explanation:
Answer:
A.) Conservation of Momentum
; use three examples of how dance can be used in somebody creating a fitness plan
1 class comment
Answer: Physical fitness can be defined as the ability of a person to perform daily routine tasks without any ailment.
Explanation:
Dance workouts can help in improving the physical fitness of the person.
This may involve improvement of the cardiovascular strength.
This may also help in improving the strength and endurance of a person.
This improves the stamina, flexibility, and composition of the body.
The dance also helps in maintaining balance and attaining the correct posture.
An object is in projectile motion if it?
Answer:
A projectile is an object upon which the only force is gravity. ... The horizontal motion of the projectile is the result of the tendency of any object in motion to remain in motion at constant velocity. Due to the absence of horizontal forces, a projectile remains in motion with a constant horizontal velocity.
I WOULD GIVE BRAINLIEST TO ANYONE THAT ANSWERS :) ✌
How would you build a device to convert the blowing of the wind into a form a car could use to drive down the street on regular tires and wheels?
Answer:
I would add a higher center of gravity, and make the car shaped in a way where wind could hit it, and the wind won't affect the car's movement whatsoever.
Explanation:
A higher center of gravity ensures that your car will take less effects from the wind, and the shape would make it barely noticeable.
It is simpler to maintain your balance the lower your center of gravity is. You can lean over more if you're sitting down than if you're standing. You can lean further to one side or the other when your center of gravity is low.
What device to convert the blowing wind to a form of a car?From a handling perspective, lower is better since it lessens weight transfer during cornering and braking and lessens the tendency to roll over.
For safe handling, the height of the vehicle's center of gravity is crucial. You are more likely to go over if your center of gravity is high, like in the case of having large or stacked-high cargo on top.
It is especially hazardous when driving around curves or when swerving to avoid hazards.
Increase the center of gravity of the vehicle and shape it so that it can be hit by wind without the wind having any impact on how the vehicle moves.
Therefore, Your car will be less affected by the wind if it has a higher center of gravity, and the shape would barely be evident.
Learn more about blow here:
https://brainly.com/question/10750178
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How much power is used if a force of 35 newtons is used to push a box a distance of 10 meters in 5 seconds?w=350j
Answer:
How much power is used if 350J of work is done when pushing a box for 5 seconds.
Explanation:
the answer is 70watts