what is the pressure on a swimmer 50 m below the surface of a lake
Answer:
P = 490500 [Pa]
Explanation:
The pressure at the bottom of a vessel and even of a lake or sea can be calculated by means of the following hydrostatic equation.
[tex]P=Ro*g*h[/tex]
where:
P = pressure [Pa] (units of pascal)
Ro = water density = 1000 [kg/m³]
g = gravity acceleration = 9.81 [m/s²]
h = elevation = 50 [m]
Now replacing:
[tex]P=1000*9.81*50\\P=490500[Pa][/tex]
How long ago did most Middle Eastern countries gain their independence?
A.
10-20 years ago
B.
50-100 years ago
C.
200-300 years ago
D.
400-500 years ago
Please select the best answer from the choices provided
A
B
C
D
Answer:
the correct answer is B
Explanation:
Answer:
.B
Explanation:
This is the answer on edge 2021
Have a good day!
A teacher places a warm bottles in a cooler filled with ice. Which statement best explains what happened over time?
A) Thermal energy will move from ice to water bottles
B) Coldness will move from the water bottles to the ice.
C) Coldness will move from the ice to the water bottlers
D) Thermal energy will move from the water bottle to the ice.
Answer:
D) Thermal energy will move from the water bottle to the ice.
Explanation:
Overtime, what happens is that thermal energy will move from the water bottle to the ice.
The water bottle is at a higher temperature compared to the ice. So, thermal energy will move from a place at higher temperature to one with lower temperature.
Thermal energy will stop moving until thermal equilibrium is attained. The water bottle will lose heat to the ice and by so doing it becomes colder. The ice will gain heat and begins to warm upExplain whether the acceleration of the moon is higher than,less or equal to that on the earth
Answer:
If we know that [tex]m < M[/tex], then acceleration of the Moon is less to that on the Earth.
Explanation:
From Newton's Law of Gravitation we know that gravitational force between Earth and Moon ([tex]F[/tex]), measured in newtons, is expressed by this formula:
[tex]F = G\cdot \frac{M\cdot m}{r^{2}}[/tex] (1)
Where:
[tex]G[/tex] - Gravitational constant, measured in cubic meters per kilogram-square second.
[tex]M[/tex] - Mass of the Earth, measured in kilograms.
[tex]m[/tex] - Mass of the Moon, measured in kilograms.
[tex]r[/tex] - Distance between centers, measured in meters.
By comparing (1) with definition of Weight, we see that gravitational acceleration experimented by Earth ([tex]g[/tex]), measured in meters per square second, is:
[tex]g = \frac{G\cdot m}{r^{2}}[/tex] (2)
If we know that [tex]m < M[/tex], then acceleration of the Moon is less to that on the Earth.
Cecily is inflating her bicycle tyre with the pump below. When she pushes the plunger down, it is doing work against the gas. This means that the plunger is transferring what to the gas particles?
The plunger is transferring energy to the gas particles.
What the plunger is transferring to the gas particles?When Cecily is applying pressure to the plunger, the gas inside is being compressed, and the speed of gas molecules increases.
When these air molecules enter the tire, adiabatically, the temperature of the gas rises.
It happens due to an increase in the average kinetic energy of the gas particles.
Thus, the gas particles receive energy from the plunger.
Learn more about the plunger, here:
https://brainly.com/question/4190018
3.
What is a star? Why does the sun appear so big whereas the other stars do not?
Ans.
an airplane normally flying at 80 km/h north encounters a wind from the west of 10km/h at right angle to its foward motion a crosswind what will its resultant velocity be ?
Answer:
v = 80.62 km/h
Explanation:
Given that,
An airplane normally flying at 80 km/h north encounters a wind from the west of 10km/h at right angle to its forward motion a crosswind.
We need to find the resultant velocity of the airplane. It can be calculated as follows :
[tex]v=\sqrt{80^2+10^2} \\\\v=80.62\ km/h[/tex]
So, the required velocity is 80.62 km/h.
The most common complaint among patients about their doctors is the time spent waiting in the doctor's office. Patients claim that doctors overbook appointments. Doctors claim that a significant number of patients fail to show or are late for their appointments. Doctors also note that as medical professionals they must tend to anyone who has need of their service. The medical profession is also uncertain because doctors never know when an emergency will occur. Considering the economic concepts of scarcity and economic resources, why must doctors book as many patients as necessary during office hours?
A doctor has the time and resources to choose how many patients to treat
A doctor, by law, must treat every patient who shows up in a medical facility
A doctor must make as much money as possible during normal business hours
A doctor's time is scarce and must be used effectively to see the most patients
Answer: B- a doctor, by law, must treat every patient who shows up in a medical facility
Explanation:
A student places an object with a mass of m on a disk at a position r from the center of the disk. The student starts rotating the disk. When the disk reaches a speed of 0.8 m/s, the object starts to slide off the disk. What is the coefficient of static friction between the object and the disk?
mass=100 g, r= 0.75 m
Answer:
The coefficient of static friction between the object and the disk is 0.087.
Explanation:
According to the statement, the object on the disk experiments a centrifugal force due to static friction. From 2nd Newton's Law, we can represent the object by the following formula:
[tex]\Sigma F_{r} = \mu_{s}\cdot N = m\cdot \frac{v^{2}}{R}[/tex] (1)
[tex]\Sigma F_{y} = N - m\cdot g = 0[/tex] (2)
Where:
[tex]N[/tex] - Normal force from the ground on the object, measured in newtons.
[tex]m[/tex] - Mass of the object, measured in newtons.
[tex]g[/tex] - Gravitational acceleration, measured in meters per square second.
[tex]v[/tex] - Linear speed of rotation of the disk, measured in meters per second.
[tex]R[/tex] - Distance of the object from the center of the disk, measured in meters.
By applying (2) on (1), we obtain the following formula:
[tex]\mu_{s}\cdot m\cdot g = m\cdot \frac{v^{2}}{R}[/tex]
[tex]\mu_{s} = \frac{v^{2}}{g\cdot R}[/tex]
If we know that [tex]v = 0.8\,\frac{m}{s}[/tex], [tex]g = 9.807\,\frac{m}{s^{2}}[/tex] and [tex]R = 0.75\,m[/tex], then the coefficient of static friction between the object and the disk is:
[tex]\mu_{s} = \frac{\left(0.8\,\frac{m}{s} \right)^{2}}{\left(9.807\,\frac{m}{s^{2}} \right)\cdot (0.75\,m)}[/tex]
[tex]\mu_{s} = 0.087[/tex]
The coefficient of static friction between the object and the disk is 0.087.
A potato with a mass of 0.25kg is resting on a table. Calculate the force that the potato exerts on the Earth.
Answer:
F = 2.45 [N]
Explanation:
The force that the potato exerts on the Earth is equal to the product of the potato mass by gravitational acceleration.
[tex]F=m*g[/tex]
where:
m = mass = 0.25 [kg]
g = gravity acceleration = 9.81 [m/s²]
[tex]F=0.25*9.81\\F=2.45[N][/tex]
These three bulbs are powered by the battery. What will happen if the middle light burns out? A. The two other bulbs will go out. B. The two other bulbs will stay on. C. Just the bulb closest to the battery will stay on. D. Just the bulb farthest from the battery will stay on.
Answer:
C
Explanation:
discuss how devastating a 7.7 - magnitude earthquake is.
Answer:
Explanation:
It’s devastating because when a earthquake is 7.7 magnitude the
In designing buildings to be erected in an area prone to earthquakes, what relationship should the designer try to achieve between the natural frequency of the building and the typical earthquake frequencies?
A) The natural frequency of the building should be exactly the same as typical earthquake frequencies.
B) The natural frequency of the building should be almost the same as typical earthquake frequencies but slightly lower
C) The natural frequency of the building should be very different frem typical earthquake frequencies
D) The natural frequency of the building should be almost the same as typical earthquake frequencies but slightly higher.
Answer:
C) The natural frequency of the building should be very different from typical earthquake frequencies
Explanation:
We shall apply the concept of resonance in this problem .
When a body is applied an external harmonic force ( forced vibration) such that natural frequency of body is equal to frequency of external force or periodicity of external force , the body vibrates under resonance ie its amplitude of vibration becomes very high .
In the present case if natural frequency of building becomes equal to the earthquake's frequency ( external force ) , the building will start vibrating with maximum amplitude , resulting into quick collapse of the whole building . So to avoid this situation , natural frequency of building should be very different from typical earthquake frequencies .
A ball rolling on the floor eventually comes to a stop. Which statement best describes this situation?
A) The energy on the macroscopic scale and the energy on the molecular scale both decreased.
B) The energy on the macroscopic scale increased, and the energy on the molecular scale decreased.
C) The energy on the macroscopic scale decreased, and the energy on the molecular scale increased.
D) The energy on the macroscopic scale and the energy on the molecular scale both remained constant.
If you have the rest please put them down :)
Answer:
Explanation:
C. The energy on the macroscopic scale decreased, and the energy on the molecular scale increased.
A. friction converts some energy on the macroscopic scale to energy on the molecular scale.
B. The mechanical energy of the system decreased because of friction.
B. The mechanical energy of the system at the beginning of the experiment is equal to the mechanical energy of the system at the end of the experiment.
B. the mechanical energy of the system decreased due to the transfer of energy on a macroscopic scale to energy on a molecular scale.
The ball rolling on the floor eventually comes to a stop which means that
the energy on the macroscopic scale decreased, and the energy on the
molecular scale increased.
What is Macroscopic scale?This is a scale in which an object can be seen with the eyes. When
an object is in motion, the ball rolls away and becomes less visible hence a
decrease in the macroscopic scale.
During motion, friction converts some macroscopic energy into molecular
scale which is why there was an increase in it.
Read more about Macroscopic scale here https://brainly.com/question/17609067
A cell phone weighing 80 grams is flying through the air at 15 m/s what is the kinetic energy
Answer:
[tex]9\:\mathrm{J}[/tex]
Explanation:
Kinetic energy is given by the following equation:
[tex]KE=\frac{1}{2}mv^2[/tex], where [tex]m[/tex] is mass in [tex]\mathrm{kg}[/tex] and [tex]v[/tex] is velocity in [tex]\mathrm{m/s}[/tex].
Since the cell phone's mass is given in grams, we need to convert this into kilograms:
[tex]80\:\mathrm{g}\cdot \frac{1\:\mathrm{kg}}{1000\:\mathrm{g}}=0.08\:\mathrm{kg}[/tex].
Therefore, the kinetic energy of the cell phone is:
[tex]KE=\frac{1}{2}\cdot 0.08\cdot 15^2=\fbox{$9\:\mathrm{J}$}[/tex].
Two spherical objects have masses of 100 kg and 200 kg. Their centers are
separated by a distance of 40 cm. Find the gravitational attraction between
them.
Answer:
8.34 x 10⁻⁶N
Explanation:
Given parameters:
Mass 1 = 100kg
Mass 2 = 200kg
Distance of separation = 40cm = 0.4m
Unknown:
Gravitational force of attraction between them = ?
Solution:
To solve this problem, we use the expression below which is derived from the Newton's law of universal gravitation:
Fg = [tex]\frac{G x mass 1 x mass 2}{d^{2} }[/tex]
G is the universal gravitation constant = 6.67 x 10⁻¹¹
d is the separation
Now;
Fg = [tex]\frac{6.67 x 10^{-11} x 100 x 200}{0.4^{2} }[/tex] = 8.34 x 10⁻⁶N
Sultan travels 40 km north then 60 km west to reach the stadium and watch the football match. What
is Sultan's displacement?
Answer:
sultan's displacement is
[tex]20 \sqrt{13} [/tex] km
The levels of organization are Cell, Tissue, Organs, ____________, and Organism. what goes in the blank?
Answer:
Organ system because multiple organs make up an organ system and multiple organ systems make up an organism
i believe Newton's 1st law is
Answer:
The first law states that if the net force is zero, then the velocity of the object is constant.
Two microwave signals of nearly equal wavelengths can gener- ate a beat frequency if both are directed onto the same microwave detector. In an experiment, the beat frequency is 100 MHz. One microwave generator is set to emit microwaves with a wavelength of 1.250 cm. If the second generator emits the longer wavelength, what is that wavelength
Answer:
the longer wavelength is 1.2552 cm
Explanation:
given that
beat frequency [tex]f_{b}[/tex] = 100 MHz = 100 × 10⁶ Hz
λ₁ = 1.250 cm = 0.0125 m
we know that beat frequency [tex]f_{b}[/tex] of two simultaneous frequencies f₁ and f₂ is expressed as;
[tex]f_{b}[/tex] = | f₁ - f₂ |
we know that microwave travels at a speed of light, so for any electromagnetic wave traveling at speed of light c with wavelength λ; frequency is;
f = c / λ
hence our beat frequency [tex]f_{b}[/tex] becomes
[tex]f_{b}[/tex] = c ( 1/λ₁ - 1/λ₂)
to find the longer wavelength, λ₂
[tex]f_{b}[/tex] = c ( 1/λ₁ - 1/λ₂)
divide both side by c
[tex]f_{b}[/tex] /c = ( 1/λ₁ - 1/λ₂)
1/λ₂ = 1/λ₁ - [tex]f_{b}[/tex] /c
λ₂ = [1/λ₁ - [tex]f_{b}[/tex] /c ]⁻¹
so we substitute in our values
we know that speed of light c = 3 × 10⁸
so
λ₂ = [ (1/0.0125) - (100 × 10⁶ /3 × 10⁸) ]⁻¹
λ₂ = [80 - 0.3333 ]⁻¹
λ₂ = [79.6667 ]⁻¹
λ₂ = 0.01255 m
λ₂ = 0.012552 × 100 cm
λ₂ = 1.2552 cm
Therefore, the longer wavelength is 1.2552 cm
Plz help this is so confusing
Answer:
5 Km/h
Explanation:
From the question given above, the following data were obtained:
Distance travelled = 10 Km
Time = 2 hours
Speed =?
Speed is simply defined as the distance travelled per unit time. Mathematically, it can be represented as:
Speed = distance travelled /time.
With the above formula, we can obtain the speed at which the duck is travelling as follow:
Distance travelled = 10 Km
Time = 2 hours
Speed =?
Speed = distance travelled /time.
Speed = 10 / 2
Speed = 5 Km/h
Thus, the duck is travelling at a speed of 5 Km/h
a) A bus of mass 760 kg requires 120 m to reach certain velocity value Vf. Ignore friction and drag forces and assume the bus engine exerts a constant forward force F. When the bus is towing a 330-kg small car, how long distance needed to reach same Vf? b) If the Vf of the bus is 28 m/s, what is the tension in the tow cable between bus and small car?
Answer:
Given : A bus of mass 760 kg requires 120 m to reach certain velocity value Vf.
the bus engine exerts a constant forward force F.
To Find : When the bus is towing a 330-kg small car, how long distance needed to reach same Vf?
Solution:
V² - U² = 2aS
V = Vf
U = 0
S = 120 m
=> Vf² - 0 = 2a(120)
=> Vf² = 240a
m = 760 kg
Force = F
F = ma
=> F =760 a
=> a = F/760
Vf² = 240F/760
Case 2 :When the bus is towing a 330-kg small car,
m = 760 + 330 = 1090 kg
a = F/1090
Vf² = 2aS
=> 240F/760 = 2 (F/1090) S
=> S = 120 x 1090 /760
=> S = 172.1 m
172.1 m distance needed to reach same Vf
Explanation:
What is a path through which electric current can flow through a wire
A person weighs 60kg. Calculate the amount of work done if he is raised 12m into the air.
Answer: I belive the answer would be 720 Joules
Explanation:
Work can be calculated by multiplying an objects weight times the distance traveled. Work is measured in joules (J).
Formula: W x D = J
W= weight
D= Distance
J= joules of energy
Hope it helps
A spring stretches by 15cm when a mass of 300g hangs down from it,if the spring is then stretched an additional 10cm and released, calculate;the spring constant,the angular velocity, amplitude of oscillation, maximum velocity, maximum acceleration of the mass,period, frequency
Answer:
0.1 m
Explanation:
It is given that,
Mass of the object, m = 350 g = 0.35 kg
Spring constant of the spring, k = 5.2 N/m
Amplitude of the oscillation, A = 10 cm = 0.1 m
Frequency of a spring mass system is given by :
Time period:
. What is the atomic number for calcium?
find the volume of an object with a density of 3.2 g/mL and a mass of 12 g.
How many joules does your 1600W electric hair dryer transfer if it takes 1 minutes to dry your hair?
____ joules
Answer:
96,000joules!!!
Explanation:
Hope this helps u
a car moved 60 meters west in 2hours what is its average velocity
Answer:
30 m/h
Explanation:
Have A Wonderful Day !!
describe measurement in our daily life