Answer:
v_t = [tex]\frac{2 g \ ( \rho_b - \rho_l ) r^2 }{9 \ \eta }[/tex]
Explanation:
Let's describe the motion and forces on the marble when it falls into the graduated cylinder filled with water.
Initially, the marble in the air falls under the influence of its weight (gravity force), when it enters the water, a friction force appears that INCREASES with SPEED and opposes the movement, this force is called Stokes force.
Fr = 6π R η v
where η is the viscosity of water
also because of this in a liquid it has an upward thrust, given by Archimedes' law, this thrust is CONSTANT
B = ρ_l g V_l
in that case the volume of liquid(V_l) is equal to the volume of the marble.
Constant force of gravity
W = mg
using the concept of density
ρ_body = m / V
W = ρ_body g V_body
we apply Newton's second law
Fr + B - W = ma
the friction force increases and the other two are constant, so acceleration decreases until reaching zero, at this point the forces are in BALANCE
Fr + B - W = 0
and the speed remains constant, being called TERMINAL SPEED
v_t = [tex]\frac{2 g \ ( \rho_b - \rho_l ) r^2 }{9 \ \eta }[/tex]
from this point on, the displacement is proportional to the time
Genes consist portions of _____.
A coconut at rest suddenly explodes into two pieces. no net external force is applied to it.One piece with mass 2m lands a distance d to the right of the starting point. The second piece has mass m. We can ignore air resistance. where dow stew swcond piece land?
Answer:
To the Left
Explanation:
why are antennas needed for radio, television, and cell phone transmission>
A. without a long antenna, the signal will not travel very far
B. the antenna allows you to direct your signal toward the intended target
C. the sound waves require a metal surface to bounce off
D. EM waves are created by oscillating electrons within the antenna
40 points + brainliest if correct please help
Answer:
A.without a long antenna, 're signal will not travel far
A bear fells from 10m long grass
From where the bear is
How does a parallel circuit change when a branch is added?
The total resistance increases, so the current in the circuit decreases.
The total resistance decreases, so the current in the circuit increases.
The total resistance increases, so bulbs shine at a lower brightness.
The total resistance decreases, so bulbs shine at a higher brightne
The distance from the center of the lens to its principal focus is called the focal length.
O A. True
O B. False
Answer:
true
Explanation:
Answer:
Explanation:
A. True
Explain why all living have genes and DNA but not all living things look the same. (Discuss, paragraph answers)
Answer:
All living organisms store genetic information using the same molecules DNA and RNA. Genes are maintained over an organism's evolution, however, genes can also be exchanged or "stolen" from other organisms.
During which radioactive decay process does the mass number of a nucleus change?
A. Beta Decay (Electron)
B. Beta Decay (Positron)
C. Alpha Decay
D. Gamma Decay
Answer:
Alpha decay
Explanation:
Answer:
C
Explanation:
Alpha Decay
How does a recessive allele “show up” to be seen?
Answer:
Recessive alleles only show their effect if the individual has two copies of the allele.
Explanation:
Dominant and Recessive Alleles If your allele pair is FF or Ff, you will have freckles. The only way you can escape a freckled face is to inherit the recessive gene from each parent, giving you the ff allele pair. In general, recessive alleles show up in your phenotype only if you have two of them.
A radioactive decay is illustrated. Which radioactive emission is a product of this decay?
A)Alpha
B)beta
C)gamma
D)positron
The radioactive decay is shown in the image attached to this answer
Answer:
Alpha
Explanation:
An alpha decay is said to have occurred when the mass number of the daughter nucleus decreases by four units and the atomic number of the daughter nucleus decreases by two units.
If we look at the equation from left to right, we will notice that the mass number of the daughter nucleus decreased by four units and the atomic of the daughter nucleus number by two units compared to that of the parent nucleus leading to the emission of an alpha particle.
What type of lens is used in the objective lens (front lens) of binoculars and why?
(Concave or convex)
Answer:
If you want to see something in the distance, you can use two convex lenses, placed one in front of the other. The first lens catches light rays from the distant object and makes a focused image a short distance behind the lens. This lens is called the objective, because it's nearest to the object you're looking at.
a car has a mass of 200kg. It is on a hill 1000m high. How much gravitational potential energy does the car have?
Answer:
Explanation:
PE = m * g * h
m = 200 kg
h = 1000 m
g = 9.81
PE = 200 * 9.81 * 1000
PE = 1962000 Joules
which subatomic particle is transferred through circuits
Answer:A third type of subatomic particle, electrons, move around the nucleus. The electrons have a negative electrical charge. An atom usually contains an equal number of positively charged protons and negatively charged electrons.
Explanation:
A father is homo….zygou dominant for green eyes, the mother is heterozygous. How many of the offspring will have green eyes?
Answer:
100%
Explanation:
Father - EE
Mother - Ee
How many valence electrons does the hydrogen and oxygen have in the following picture?
Answer:
can u make the picture less blurry pls
Explanation:
A person is heterozygous for big ears, what is their genotype?
./././././././././././././././././././.
it's on the screenshot, apparently it was inappropitae so i couldnt submit it here
Which material is a conductor?
A. chalk
B. lead
C. leather
D. paper
E. rubber
B. Lead is a conductor....
In the diagram, R1 = 40.0 ohm, R2 = 25.4 ohm, and R3 = 70.8 ohm. What is the equivalent resistance of the group?
The resistors [tex]R_1 and R_2 [/tex]are in series connection, so the equivalent resistance of [tex]R_1 and R_2[/tex] will be their sum.
[tex] \boxed{ \mathrm{R_t = R_1 + R_2}}[/tex]
[tex]R_t= 40 + 25.4[/tex][tex]R_t= 65.4 \: \: ohms[/tex]Now, the equivalent resistance of [tex](R_1 and R_2)[/tex] and [tex]R_3 [/tex] is the total resistance of the circuit, and since they are in parallel connection, Total resistance :
[tex] \mathrm{ \dfrac{1}{ R_{eq}}} = \dfrac{1}{65.4} + \dfrac{1}{70.8} [/tex][tex] \dfrac{1}{R_{eq}} = \dfrac{65.4 + 70.8}{4630.32} [/tex][tex] \frac{1}{R_{eq}} = \dfrac{136.2}{4630.32} [/tex][tex]R_{eq} = \dfrac{4630.32}{136.2} [/tex][tex]R_{eq} = 33.996 \: \: ohms[/tex][tex] \boxed{ \mathrm{R_{eq} = 34 \: ohms}} \: (approx)[/tex]_____________________________
[tex]\mathrm{ \#TeeNForeveR}[/tex]
???????????!??!!!!!!!!
A man is driving his 1100 kg car at 36 km/h on a straight freeway. After accelerating for 30 seconds, the car
has a speed of 108 km/h. How much work did the engine do during the 30 seconds?
Answer:
W = 439998 J = 439.99 KJ
Explanation:
First, we will calculate the acceleration of the car by using the first equation of motion:
[tex]v_f = v_i + at\\\\a = \frac{v_f-v_i}{t}[/tex]
where,
a = acceleration = ?
vf = final speed = [tex]108(\frac{km}{h})(\frac{1000\ m}{1\ km})(\frac{1\ h}{3600\ s})[/tex] = 30 m/s
vi = initial speed = [tex]36(\frac{km}{h})(\frac{1000\ m}{1\ km})(\frac{1\ h}{3600\ s})[/tex] = 10 m/s
t = time = 30 s
Therefore,
[tex]a = \frac{30\ m/s - 10\ m/s}{30\ s}[/tex]
a = 0.67 m/s²
Now, we will calculate the force applied by the engine:
F = ma
where,
F = force = ?
m = mass = 1100 kg
Therefore,
F = (1100 kg)(0.67 m/s²)
F = 733.3 N
Now, we will calculate the distance covered by the car by using the second equation of motion:
[tex]s = v_it+\frac{1}{2}at^2\\\\s = (10\ m/s)(30\ s)+\frac{1}{2} (0.67\ m/s^2)(30\ s)^2[/tex]
s = 600 m
Now, the work done (W) by engine can be calculated as follows:
W = Fs
W = (733.3 N)(600 m)
W = 439998 J = 439.99 KJ
In a motor, electrical current enters through the brushes.
Please select the best answer from the choices provided
T
F
THE ANSWER IS TRUE
Answer: ITS T
Explanation:
In a motor, electrical current enters through the brushes. TRUE.
What is the amount of work done when JoAnne throws a baseball 2 meters at a force of 40
newtons?
Answer:
Amount of work done by Joanne = 80 joule
Explanation:
Given:
Displacement of ball = 2 meters
Force applied = 40 newtons
Find:
Amount of work done by Joanne
Computation;
Work done = Force applied x Displacement
Amount of work done by Joanne = Force applied x Displacement of ball
Amount of work done by Joanne = 40 x 2
Amount of work done by Joanne = 80 joule
If 30.45 grams of water is to be heated up 3.3 degrees to make baby
formula, how much heat must be added? The specific heat of water is
4.18 J/g °C.
A. 420 J
B. 281 J
C. 1604 J
D. 410 J
Answer:
A. 420 J
Explanation:
Given the following data;
Mass = 30.45 g
Specific heat capacity = 4.18 J/g °C.
Temperature = 3.3°C
To find the quantity of heat;
Heat capacity is given by the formula;
[tex] Q = mct [/tex]
Where;
Q represents the heat capacity or quantity of heat.
m represents the mass of an object.
c represents the specific heat capacity of water.
t represents the temperature.
Substituting into the equation, we have;
[tex] Q = 30.45 * 4.18 * 3.3 [/tex]
Q = 420.03 ≈ 420 Joules
Alejandro camina 250 metros en linea recta durante 5 minutos y regresa a su mismo camino a su punto de partida en 7 minutos. ¿cual es la distancia total recorrida? ¿cual es la velocidad en m/s? ¿cuanto vale su desplazamiento total?
Un móvil posee un movimiento uniformemente acelerado, con una velocidad inicial de 20 m/s y aceleración 1,5 m/s. ¿Qué velocidad tendrá cuando hayan transcurrido 2 minutos? ¿Qué espacio habrá recorrido durante ese tiempo?
Answer:
La velocidad que tendrá el móvil cuando hayan transcurrido 2 minutos es 200 m/s.
El espacio que habrá recorrido el móvil durante 2 minutos es 13200 metros.
Explanation:
El movimiento rectilíneo uniformemente variado o MRUV es un movimiento que ocurre sobre una línea recta con aceleración constante. En otras palabras, un cuerpo realiza un movimiento rectilíneo uniformemente variado cuando su trayectoria es una línea recta y su aceleración es constante y distinta de 0. Esto implica que la velocidad aumenta o disminuye su módulo de manera uniforme.
La velocidad que tendrá un móvil luego de un tiempo t será:
v= v0 + a*t
donde v0 es la velocidad inicial y a es la aceleración.
En este caso v0= 20 m/s, a=1,5 m/s² y t=2 minutos= 120 segundos. Reemplazando y resolviendo se obtiene:
v= 20 m/s + 1.5 m/s²* 120 segundos
v= 200 m/s
La velocidad que tendrá el móvil cuando hayan transcurrido 2 minutos es 200 m/s.
La expresión de la posición en función del tiempo para el movimiento uniformemente variado es:
x= x0 + v0*t + [tex]\frac{1}{2}[/tex] *a*t²
donde x0 es la posición inicial, v0 es la velocidad inicial y a es la aceleración.
En este caso x0= 0 m, v0= 20 m/s, a=1,5 m/s² y t=2 minutos= 120 segundos. Reemplazando y resolviendo se obtiene:
x= 20 m/s* 120 s + [tex]\frac{1}{2}[/tex] * 1.5 m/s² *(120 s)²
x= 2400 m + 10800 m
x= 13200 m
El espacio que habrá recorrido el móvil durante 2 minutos es 13200 metros.
The gravitational force is 2336 N for an object that is 4.15 x 10^6 m above the surface of the Earth? The radius of the Earth is 6.378 x 10^6 m. (Earth's mass is 5.97 x 10^24 kg) What is the mass of the object above earth?
Answer:
34kg
Explanation:
Fundamentally, pressure is defined as force per unit area. What is the source of the force in a gas sample? A) The force is from gravity acting on the particles. B) The force is composed of the sum of the collisions only between gas molecules. C) The force is composed of the sum of the collisions only between the gas molecules and the container. D) The force is composed of the sum of all collisions--between the gas molecules, each other and the container. E) The force was imparted to the container in its initial filling, a transfer of momentum.
Answer:
Option C
Explanation:
Given
Pressure = Force /Area
For any gas sample, force is defined as basically the force exerted by the gas molecules when they strike the surface (with in which they are contained) and bounce back.
Hence, Option C is the correct
PLEASE HELP!! 10 points each!!!
What is alchemy? How is artificial transmutation like alchemy? Use examples to support your answer.
Answer:
an alchemy is
the medieval forerunner of chemistry, concerned with the transmutation of matter, in particular with attempts to convert base metals into gold or find a universal elixir.
A planet orbits a sun in a clockwise elliptical orbit as shown in the diagram below
Bubble in the letter representing the position or choose e if it is constant
At which position does the planet have the greatest gravitational energy?
Answer:
Greatest gravitational energy is at "C".
The planet has to do work "against" the field to get to "C".
Also, if m v R (angular momentum) is constant then as R increases v must decrease for this term to be constant and KE = 1/2 M v^2 must decrease also to get to point C.
how does a force pumb works
Answer:
A force pump can be used to raise water by a height of more than 10m, the maximum height allowed by atmospheric pressure using a common lift pump.
In a force pump, the upstroke of the piston draws water, through an inlet valve, into the cylinder. On the downstroke, the water is discharged, through an outlet valve, into the outlet pipe.