Answer:
D
Explanation:
Cá xương, chim, thú, cá sấu không có sự pha trộn máu giàu O2 và máu giàu CO2 ở tim vì tim cá có 2 ngăn, tim các loài chim, thú, cá sấu có 4 ngăn
Squids rely on jet propulsion to move around in water. A 1.5 kg squid at rest suddenly expels 0.12 kg of water backward to quickly get itself moving forward at 2.8 m/s. If other forces (such as the drag force on the squid) are ignored, what is the speed with which the squid expels water
Answer:
The speed of water is 32.2 m/s .
Explanation:
Mass of squid, M = 1.5 kg
mass of water, m = 0.12 kg
velocity of squid, V = - 2.8 m/s
Let the speed of water is v.
Use the conservation of momentum,
Momentum before expelling the water momentum after expelling water
M x 0 = (M - m) x V + m x v
0 = - (1.5 - 0.12) x 2.8 + 0.12 v
3.864 = 0.12 v
v = 32.2 m/s
Name the type of relationship between current and potential difference for a resistor at constant temperature. [
The current flowing through a resistor at a constant temperature is directly proportional to the potential difference across it. This is called Ohm's law
The radius of the base of a wooden cylinder 2m and its altitude is 7m. What is its mass?
Answer:
88 m ^2
Explanation:
Think of a body which is at rest but not in equilibrium
Answer:
I think the sun is the right answer
Even though you praise your dog for sitting inside on his bed and chewing the bone you gave him, your dog insists on going outside and burying his bone. This is MOST likely an example of:
Answer:
dog
Explanation:
Fifty (50) grams of vinegar and (2) grams of baking soda are mixed together. A bubbling reaction takes place. The mixture is weighed again and now weighs 49 grams. How do you explain the missing weight?
Answer:
the gas that escaped from the mixture contained the missing weight
1. How much heat energy ( Q ) is required to heat 2.0 kg of copper from 30.0 oC to 80.0 oC?
Answer:
38500
Explanation:
I looked it up so it may be wrong
To what height, h, would the pendulum bob rise after a single swing if it was being released from the height of 0.80 m
Answer:
0.80 m
Explanation:
Neglecting friction, the total mechanical energy of the pendulum is constant.
E = K + U where K = kinetic energy and U = potential energy.
At its release point of 0.80 m, the pendulum bob has a mechanical energy which is equal to its potential energy, since, its initial kinetic energy is zero. By the time the bob swings to the other end, it has a mechanical energy equal to it initial potential energy since total energy is conserved.
Neglecting friction, the pendulum bob would swing back to its original height of 0.80 m since the total mechanical energy is conserved and at its highest point, it is purely potential energy.
So, the height the pendulum bob swings to after release from a height of 0.80 m neglecting fiction is 0.80 m.
a. What is the physical quantity in which force is divided by area called?
Any guess 50 pts + brainlist if correct
Answer:
pressure
Explanation: pressure=force/area
Answer:
The quantities that can be measured are called physical quantities.....
Wat is acceleration!!!!!
Answer:
Acceleration is the rate of change of velocity with time.its system international unit is meters per second square.
I hope this helps
Hello! I am taking physics H on edge 2021 and if someone could give me the completed Electromagnetic Fields Plan an Investigation student guide/lab report I would be eternally grateful!!!
To create an electromagnetic field, a magnetic and electric field is involved.
An Electromagnetic field planElectromagnetic field consists of both electric and magnetic fields which are produced by human activities through the use of electricity.
With the above definition of electromagnetic field, it's production will involve:
Magnetic field: These fields are created by the magnets.Electric field: These fields are created by electric charges.These fields oscillate in perpendicular planes with respect to each other, and are in phase.
Therefore, to create an electromagnetic field, a magnetic and electric field is involved.
Learn more about electromagnetic field here:
https://brainly.com/question/1594186
Answer:
I need this as well
Explanation:
If the poster got the project, please let me know. I'm struggling on this unit and if you don't want to give out the project, help is appreciated too! thanks
Can someone help me please this test is very important
Answer:
Friction is caused in roller coasters by the rubbing of the car wheels on the track and by the rubbing of air (and sometimes water!) against the cars.
Explanation:
If there is 3.4 m3 of methane gas in a container with a pressure of 18.9 atm and the container expands until the methane has a pressure of 2.2 atm, what is the final volume of the methane? Temperature is constant at 305 K. A. 12.23 m3 B. 141.37 m3 C. 29.21 m3 OD. 2.53 m3
Answer:
C. 29.21 m³
Explanation:
Given the following data;
Initial volume, V1 = 3.4 m³Initial pressure, P1 = 18.9 atmFinal pressure, P2 = 2.2 atmTo find the final volume, we would use Boyle's law;
Boyles states that when the temperature of an ideal gas is kept constant, the pressure of the gas is inversely proportional to the volume occupied by the gas.
Mathematically, Boyles law is given by;
PV = K
[tex] P_{1}V_{1} = P_{2}V_{2} [/tex]
Making V2 the subject of formula, we have;
[tex] V_{2} = \frac {P_{1}V_{1}}{P_{2}} [/tex]
Substituting the values into the formula, we have;
[tex] V_{2} = \frac {18.9 * 3.4}{2.2} [/tex]
[tex] V_{2} = \frac {64.26}{2.2} [/tex]
Final volume, V2 = 29.21 m³
Why do ionic compounds make good conductors when dissolved in water?
Answer: The correct answer is B- The ions are free to move in water and carry an electric charge.
A 2.0kg object is dropped from a height of 30m.
After it drops for 2.0 seconds, what is its kinetic
energy and what is its potential energy?
(Assume no air resistance.)
Answer:
1) The kinetic energy of the object after it drops for 2.0 seconds is approximately 384.9 Joules
2) The potential energy of the object after it drops for 2.0 seconds is approximately 204 J
Explanation:
1) The given mass of the object, m = 2.0 kg
The height from which the object is dropped, h = 30 m
The kinetic energy of the object after it drops for 2.0 seconds = Required
Kinetic energy, K.E. = (1/2)·m·v²
Where;
v = The velocity of the object
The kinematic equation for finding the velocity of the object is presented as follows;
v = u + g·t
Where;
u = The initial velocity of the object = 0
g = The acceleration due to gravity of the object ≈ 9.81 m/s²
t = The time of motion of the object = 2.0 seconds
∴ The velocity after 2 seconds, v ≈ 0 + 9.81 m/s² × 2 s = 19.62 m/s
The kinetic energy, K.E. after 2 seconds as the object drops is given as follows;
[tex]K.E._{(after \ two \ seconds)}[/tex] = (1/2) × 2.0 kg × (19.62 m/s)² = 384.9444 J ≈ 384.9 J
2) The total energy, M.E. of the object at the top, h = 30 m, u = 0, is given as follows;
The total mechanical energy, M.E. = P.E. + K.E.
M.E. = m·g·h + (1/2)·m·u²
∴ M.E. = 2.0 kg × 9.81 m/s² × 30 m + 0 = 588.6 J
M.E. = 588.6 J
Given that the total mechanical energy, M.E., is constant, we have;
At 2.0 seconds, M.E. = 588.6 J , K.E. ≈ 384.9 J, P.E. = M.E. - K.E.
∴ P.E. = 588.9 J - 384.9 J ≈ 204 J
The potential energy after it drops 2.0 seconds, P.E. ≈ 204 J
1. Find the temperature when the degrees of the Celsius scale will be one fifth of the corresponding degrees of the Fahrenheit scale
2. How much heat is necessary to warm 500g of water from 20°C to 65°C?
Answer:
F = 9/5 C + 32 conversion from C to F
F = 9/5 * F/5 + 32
25 F = 9 F + 800
16 F = 800
F = 50
Check:
C = 5/9 ( F - 32) = 5/9 (50 - 32) = 10 as requested
Q = c m change in temp
Q = 1 cal/gm-deg C * 500 gm * 45 deg C = 22,500 calories
50 Fahrenheit heat required.
How much heat required?Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems.
F = 9/5 C + 32 conversion from C to F
F = 9/5 * F/5 + 32
25 F = 9 F + 800
16 F = 800
F = 50
The answer is 50 Fahrenheit.
Learn more about heat transfer
https://brainly.com/question15086449
#SPJ2
1.Convert 340 cm into m *(answer=0.34m)
2.What is the weight of potatoes of mass 75kg on the surface of the earth? *(ans=735 N)
[g=9.8 m/s^2
[g=9.8 m/s^2]
3.The weight of body is 420 N.Calculate its mass. *(42.857 kg)*
Answers are all given so i just need the process please (i will mark you brainliest please..
Answer:
1.for the first one 100centimeters make 1 meter therefore
100cm-1m
340cm-x
340/100
=3.4
the answer is supposed to be 3.4, maybe there's a mistake with the question or the answer
2.the weight of a body is given by the formula
mass×gravity,in this case the mass is 75kg and the gravity is 9.8
weight=75×9.8
=735N
3.for this one the mass of a body is given by the formula
mass=weight/gravity
=420/9.8
=42.8kg
I hope this helps
three letters (JET) are placed in front of a plane mirror the image formed is in what arrangement???
Answer:
TEJ as this is a thing you wont get
We reduce friction in machines? why
Answer:
friction reduces the efficiency of machines, thus we must reduce the friction force that is acting upon it.
Answer:
Because it causes a lot of wear and tear in machine parts that move against each other. It erodes the surfaces and destroys their symmetries
Explanation:
if a person buys 10 kg apples in himalayan region and sells in terai region will he get profit or loss. why?
Answer:
he will be in profit
Explanation:
Himalayan region are high above the sea level so the gravity will be less there compared to the Terai region
Terai lies way below he Himalayan region so the pull of gravity will be more compared to Himalayan region
that's why he will be in profit but not loss
Un cuerpo tiene una rapidez inicial de 5 m/s y una aceleración de 6 m/s2 . Calcular la rapidez y la distancia recorrida durante los primeros 9 segundos del movimiento. Resolver el ejercicio por medio de tablas y gráficas y luego resolverlo por medio de las fórmulas de movimiento. POR FAVOR AYUDAAAA... ES PARA MAÑANA ;-;
Encontramos que la distancia recorrida en los primeros 9 segundos es 288 metros.
Los datos dados son:
El cuerpo tiene una rapidez inicial de 5 m/s
El cuerpo tiene una aceleración de 6 m/s^2
Queremos calcular la distancia recorrida durante los primeros 9 segundos de movimiento.
Lamentablemente no contamos con los gráficos ni las tablas, así que se procede a obtener las ecuaciones de movimiento.
La aceleración será:
a(t) = 6m/s^2
Para la ecuación de la velocidad tenemos que integrar la ecuación de arriba, obteniendo:
v(t) = (6m/s^2)*t + v0
Donde v0 es la rapidez inicial, que conocemos es igual a 5 m/s, así tenemos:
v(t) = (6m/s^2)*t + 5m/s
Para la ecuación de la posición debemos integrar nuevamente, así obtendremos:
p(t) = (1/2)*(6m/s^2)*t^2 + (5m/s)*t + p0
Donde la p0 es la posición inicial, la cual podemos definir como p0 = 0m
p(t) = (3m/s^2)*t^2 + (5m/s)*t
Para encontrar la distancia recorrida en los primeros 9 segundos, simplemente debemos remplazar t por 9s en la ecuación de posición:
p(9s) = (3m/s^2)*(9s)^2 + (5m/s)*9s = 288 m
Si querés aprender más sobre ecuaciones de movimiento, podés leer:
https://brainly.com/question/17123407
determjne the density of liquid whose relative density is 1.25 given that the density is 1000kgm-3
Explanation:
Relative density=density of liquid÷density of water
1.25=x ÷ 1000
x=1.25 × 1000
x=1250kgm^-3
A tightrope walker is walking between two buildings holding a pole with length L=14.0 m, and mass mp=17.5 kg. The daredevil grips the pole with each hand a distance d=0.595 m from the center of the pole. A bird of mass mb=560 g lands on the very end of the left‑hand side of the pole. Assuming the daredevil applies upward forces with the left and right hands in a direction perpendicular to the pole, what magnitude of force Fleft and Fright must the left and right hand exert to counteract the torque of the bird?
Answer:
F = 32.28 N
Explanation:
For this exercise we must use the rotational equilibrium relation
Σ τ = 0
In the initial configuration it is in equilibrium, for which all the torque and forces are compensated. By the time the payment lands on the bar, we assume that the counter-clockwise turns are positive.
W_bird L / 2 - F_left 0.595 - F_right 0.595 = 0
we assume that the magnitude of the forces applied by the hands is the same
F_left = F_right = F
W_bird L / 2 - 2 F 0.595 = 0
F = [tex]\frac{m_{bird} \ g L} { 4 \ 0.595}[/tex]
we calculate
F = 0.560 9.8 14.0 /2.38
F = 32.28 N
an electron is moving at 3.6 x 10^3 m/s. a photon with what wavelength would have the same momentum????
Answer:
The wavelength of the photon that would have the same momentum as the electron is 202.2180996 nm
Explanation:
The velocity of the electron, v = 3.6 × 10³ m/s
The momentum of an electron, [tex]p_e[/tex] = m × v
Where;
v = The mass of the electron = 9.109 × 10⁻³¹ kg
∴ [tex]p_e[/tex] = 9.109 × 10⁻³¹ kg × 3.6 × 10³ m/s = 3.27924 × 10⁻²⁷ kg·m/s
According to the de Broglie equation, the momentum of a photon, p, is given as follows;
p = h/λ
Where;
h = 6.63 × 10⁻³⁴ J·s
λ = The wavelength of the photon
∴ λ = h/p
According to the question, we have;
p = [tex]p_e[/tex] = 3.27924 × 10⁻²⁷ kg·m/s
∴ λ = 6.63 × 10⁻³⁴ J·s/(3.27924 × 10⁻²⁷ kg·m/s) = 2.02180993 × 10⁻⁷ m
The wavelength of the photon, λ = 2.02180993 × 10⁻⁷ m = 202.2180993 × 10⁻⁹ m = 202.2180993 nm.
Con lắc lò xo có độ cứng k = 100N/m được gắn vật có khối lượng m=0.1kg, kéo vật ra khỏi vị trí cân bằng 1 đoạn 5cm rồi buông tay cho vật dao động. Tính vmax vật có thể đạt được
Answer:
The maximum velocity is 1.58 m/s.
Explanation:
A spring pendulum with stiffness k = 100N/m is attached to an object of mass m = 0.1kg, pulls the object out of the equilibrium position by a distance of 5cm, and then lets go of the hand for the oscillating object. Calculate the achievable vmax.
Spring constant, K = 100 N/m
mass, m = 0.1 kg
Amplitude, A = 5 cm = 0.05 m
Let the angular frequency is w.
[tex]w = \sqrt{K}{m}\\\\w = \sqrt{100}{0.1}\\\\w = 31.6 rad/s[/tex]
The maximum velocity is
[tex]v_{max} = w A\\\\v_{max} = 31.6\times 0.05 = 1.58 m/s[/tex]
"Measurement is essential in our life. Justify the statement.
Explanation:
Measurement plays an important role in our daily lives because they are useful to do basic tasks, such as taking the temperature of a child with the help of a thermometer,making time estimations,measure out medicines and find out weights, areas and volumes of different substances
Numerical problems:
a. convert the following as instructed:
i) 340 cm into m
ii)86400 seconds into day
Answer:
a=3.4m because of the m
b=1day because 86400=a day
a ball was changed vertically upwards with kinetic energy 200 joule what will be the total energy and Midway
Answer:
Part 1; The total energy = Constant = 200 J
Part 2; Midway, the potential energy = The kinetic energy = 100 J
Explanation:
Part 1
According to the first law of thermodynamics, energy is neither created nor destroyed but changed from one form to another
The total (mechanical) energy = Potential energy + Kinetic energy = Constant
The kinetic energy given to the ball changed vertically up = 200 J
Potential energy = Mass, m × Gravity, g × Height, h
Given that the mass m of the ball and the acceleration due to gravity, g, remain the same, we have;
Potential energy ∝ The height of the ball
The potential energy at ground level = 0 J (Height , h = 0)
∴ The total (mechanical) energy = 0 J + 200 J = 200 J
At the maximum height, the ball momentarily stops, and the kinetic energy = 0 J
Therefore;
The potential energy of the ball at the maximum height, [tex]h_{max}[/tex], [tex]P.E._{max}[/tex] = 200 J
∴ [tex]P.E._{max}[/tex] = m·g·[tex]h_{max}[/tex] = 200 J
Part 2
At midway we have, the height, h = ([tex]h_{max}[/tex])/2
Therefore, [tex]P.E._{Midway}[/tex] = (m·g·([tex]h_{max}[/tex]))/2 = ([tex]P.E._{max}[/tex])/2 = (200 J)/2 = 100 J
The potential energy midway = 100 J
The remaining 200 J - 100 J = 100 J is the kinetic energy remaining in the ball
The kinetic energy midway = 100 J
Therefore, the total energy midway = 100 J + 100 J = 200 J
If the power of a working system(machine) is 2088.8 watts then its power in horsepower will be: A. 1hp B. 2.7hp C. 2.9hp D. 2.8hp
Answer:
D. 2.8 hp
Explanation:
1 hp=746 watts
2088.8÷746= 2.8
: 1 khối khi lý tưởng nhận được nhiệt lượng 200J, khi đó khí nở ra đẩy pittong bằng 1 công 80J.
Vậy nội năng Của khí là bao nhiêu
Answer:
DU = 120 Joules
Explanation:
Given the following data;
Quantity of energy = 200 J
Work = 80 J
To find the change in internal energy;
Mathematically, the change in internal energy of a system is given by the formula;
DU = Q - W
Where;
DU is the change in internal energy.
Q is the quantity of energy.
W is the work done.
Substituting into the formula, we have;
DU = 200 - 80
DU = 120 Joules
