Answer:
about 42.35 m/s
Explanation:
Use the equation for accelerated motion (g), and with zero initial velocity that doesn't include time:
[tex]v_f^2=v_i^2+2\,a\,\Delta x[/tex]
which for our case would reduce to:
[tex]v_f^2=v_i^2+2\,a\,\Delta x\\v_f^2=0+2\,9.8\,(91.5)\\v_f^2= 1793.4\\v_f=\sqrt{1793.4} \\v_f \approx 42.35[/tex]
then the velocity just before hitting would be about 42.35 m/s
A power cycle operating between hot and cold reservoirs at 500 K and 300 K, respectively, receives 1000 kJ by heat transfer from the hot reservoir. The magnitude of the energy discharged by heat transfer to the cold reservoir must satisfy
Answer:
The value is [tex]Q_l \ge 600\ k J[/tex]
Explanation:
From the question we are told that
The temperature of hot is [tex]T_h = 500 \ K[/tex]
The temperature of cold is [tex]T_c = 300 \ K[/tex]
The energy received is [tex]E = 1000 \ kJ = 1000 *10^{3 } \ J[/tex]
Generally the maximum thermal efficiency of the engine is mathematically represented as
[tex]\eta = \frac{T_h - T_c}{T_h}[/tex]
=> [tex]\eta = \frac{500 - 300}{500}[/tex]
=> [tex]\eta = 0.4[/tex]
Generally the thermal efficiency of the engine is
[tex]\eta_t = \frac{Q - Q_l}{Q}[/tex]
Here [tex]Q_l[/tex] is the heat energy rejected
Generally the thermal efficiency must be less than or equal to the maximum thermal efficiency
So
[tex]\frac{Q - Q_l}{Q} \le 0.4[/tex]
=> [tex]\frac{1000 *10^{3} - Q_l}{1000 *10^{3} } \le 0.4[/tex]
the change in inequality sign is because [tex]1000*10^{3}[/tex] which was dividing started multiplying
=> [tex]Q_l \ge 1000*10^{3} - 400*10^{-3}[/tex]
=> [tex]Q_l \ge 600*10^{3} \ J[/tex]
=> [tex]Q_l \ge 600\ k J[/tex]
what are Newton's 3 laws
Answer:
Newton 3 laws
Explanation:
1.object will not change its motion unless a force acts on it . 2.the force on an object is equal to it's time mass on acceleration. 3. When 2 o jecys interact they apply forces to each other of equal.
Calculate the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I. (Note the loop and wire are not in electrical contact.)
Answer:
The magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I is [tex]\pi[/tex] or 3.14
Explanation:
The magnetic field at center of a circular loop is given by
[tex]B = \frac{\mu _{o}I }{2R}[/tex]
Where B is the magnetic field
[tex]\mu _{o}[/tex] is the free space permeability constant ( [tex]\mu _{o}[/tex] = 4π × 10⁻⁷ N/A²)
[tex]I[/tex] is the current
and [tex]R[/tex] is the radius
For the magnetic field of a long straight wire, it is given by
[tex]B = \frac{\mu _{o}I }{2\pi R}[/tex]
Where B is the magnetic field
[tex]\mu _{o}[/tex] is the free space permeability constant ( [tex]\mu _{o}[/tex] = 4π × 10⁻⁷ N/A²)
[tex]I[/tex] is the current
and [tex]R[/tex] is the distance from the wire
Then, to calculate the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I, that will be
[tex]\frac{\mu _{o}I }{2R} \div \frac{\mu _{o}I }{2\pi R}[/tex]
= [tex]\frac{\mu _{o}I }{2R} \times \frac{2\pi R }{\mu _{o}I}[/tex]
= [tex]\pi[/tex]
(NOTE: [tex]\pi[/tex] = 3.14)
Hence, the magnetic field at the center of a circular current loop of radius R divided by the magnetic field at a distance R away from a very long straight wire carrying the same current value I is [tex]\pi[/tex] or 3.14.
Question 11 of 15
When hydrogen is attached to the more highly electronegative oxygen atom in
a water molecule,
A. the electronegative atom becomes strongly positive
B. the hydrogen atom becomes partially positive
O C. the oxygen atom becomes partially negative
If answer is right WILL GIVE BRAINLIEST
D. the hydrogen atom becomes partially negative
Answer:
I'm leaning twards A
Explanation:
An airplane flying at 119 m/s is accelerated uniformly at the rate of 0.5 m/s2 for 10
seconds. What is its final speed?
Answer:
124m/s
Explanation:
v=u+at
v=119+(0.5×10)
v=119+5
v=124m/s
Which statement describes S waves? A. They move side to side.B.They arrive betore P waves. C. They travel through liquids D. They occur at Earth's surtace.
Answer: they move side to side
Explanation:
i took the test
1) A rigid tank contains 2 kg of 134a refrigerant at 800 kPa and 120°C. Determine tank volume and total internal energy.
Answer:
V = 0.07525 [m³]
U = 655.74 [kJ]
Explanation:
To solve this problem we must use the superheated refrigerant table for refrigerant 134a. The attached image shows the specific volume and specific internal energy values for a pressure of 800 [kPa] and a temperature of 120 [°C].
m = mass =2 [kg]
the specific volume = v = 0.037625 [m³/kg]
The volume of the tank can be found using the following expression:
V = v*m
V = 0.037625*2 = 0.07525 [m³]
The Specific internal energy = u = 327.87 [kJ/kg]
U = u*m
U = 327.87*2 = 655.74 [kJ]
I am so close to wanting to drop out of physics
I'm in college and idk why physics has to be this tough. I took physics back in high school, and it was super easy & I had a really nice teacher.
But now that I'm in college, my professor does no help and literally 60 people dropped out of his class bc his class is hard. I am going to fail my midterm this week. idk what to do and Im sick and tired but its a requirement.
I literally wanna drop out of college bc of physics
Answer: Dont drop out i know school can be a headache but if you try you can accomplished anything.
Explanation:
Answer:
college vs high school.
Explanation:
hello! first, i see the comparison between college and highschool. remember that college professors are much more strict. they dont give participation awards or guide you. this is the time to push yourself! your so close to your goal, why give up from one class? you got this! every question you get wrong or right is a step closer to understanding it better. dont give up. i hope i could help!
A 2070 kg space station orbits Earth at an altitude of 5.37×105 m. Find the magnitude of the force with which the space station attracts Earth. The ma
Answer:
9.9 × 10^-16N
Explanation:
Given that a 2070 kg space station orbits Earth at an altitude of 5.37×105 m. Find the magnitude of the force with which the space station attracts Earth.
Calculating the gravitational field strength.
g = Gm/R^2
Where G = 6.67408 × 10-11 m3 kg-1 s-2
g =(6.67408 × 10-11 × 2070)/5.37 × 10^5
g = 1.38069×10^-7 / 2.88369^11
g = 4.788×10^-19 m/s
Force F = mg
Substitute g into the formula
F = 2070 × 4.79×10^-19
F = 9.9 × 10^-16N
Write the vectors labeled A, B and C with rectangular coordinates.
Focus on vector A. Start at the base of the vector which is at (1,1)
Then notice how we have to move 3 units to the right and 2 units up to get to the tip of the vector where the arrow is located. So this is at (4,3)
The fact that we moved 3 units to the right and 2 units up means that vector A is <3, 2>
So we'll type 3 in the first box and 2 in the second box.
======================================================
We use the same idea for vector B
Start at the base and move to the tip. Doing so has us move 1 unit left and 3 units down.
Vector B = <-1, -3>
We type -1 in the first box, and -3 in the second box.
======================================================
Finally onto vector C
Start at the base (0,0). To move to the tip, we need to go 3 units left and 3 units up
Vector C = <-3, 3>
-3 goes in the first box and 3 goes in the second box
======================================================
In general, vectors are useful to tell us a specific direction in which to go. They're useful in physics to determine how exactly a force is being applied, or how a particle is moving.
If a wave is traveling at a constant speed, and the frequency increases, what would happen to the wavelength?
It would increase
It would decrease.
It would remain constant.
It would drop to zero.
If a wave is traveling at a constant speed, and the frequency increases, the wavelength would decrease.
What is wavelength?The wavelength is the distance between the adjacent crest or trough of the sinusoidal wave. The wavelength is the reciprocal of the frequency of the wave.
Wavelength λ = 1 / frequency
The wavelength and frequency are inversely related to each other. So, when frequency is increased, the wavelength increases.
Thus, the wavelength of would decrease if the frequency increases.
Learn more about wavelength.
https://brainly.com/question/13533093
#SPJ2
Answer:
B. It would decrease
Explanation:
how is the process of finding the mass of a gas different from that of finding the mass of a liquid why is the difference necessary
answer
prove that p = d g h
Answer:
Proving LHS=RHS
Explanation:
Given
p=dgh
Multiplying by 0 on both sides of the equations
p×0=dgh×0
0=0
:- Hence proved
A mountain biker is climbing a steep 20° slope at a constant speed. The cyclist and bike have a combined weight of 800 N. What can you say about the magnitude of the normal force of the ground on the bike?
Answer:
Normal force = 751.75 N
Explanation:
It is given that,
The combined weight of the cyclist and the bike is 800 N
We need to find the magnitude of the normal force of the ground on the bike. It can be given by the formula as follows :
[tex]N=mg\cos\theta[/tex]
mg = W, combined weight of cyclist and bike
[tex]N=W\cos\theta\\\\N=800\times \cos(20)\\\\N=751.75\ N[/tex]
So, the magnitude of the normal force of the ground on the bike is 751.75 N.
The magnitude of the normal force of the ground on the bike is 751.752 N
The formula for that will be used to calculate the normal force of the ground on the bike is expressed as:
[tex]N= Fcos \theta[/tex]
F is the combined weight
[tex]\theta[/tex] is the angle of inclination
Given the following paramters
F = 800 N
[tex]\theta[/tex] = 20 degrees
Substitute the given parameters into the formula:
[tex]N=800 \times cos20^0\\N=800 \times 0.9397\\N=751.752N[/tex]
Hence the magnitude of the normal force of the ground on the bike is 751.752 N
Learn more here: https://brainly.com/question/12408868
What is a factor in an experiment that can be changed or it can be kept the same?
Answer: If you are performing an experiment on the effect of spraying plants with different chemicals, you would try to maintain the same pressure and maybe the same volume when spraying your plants. The independent variable is the one factor that you are changing. It is one factor because usually in an experiment you try to change one thing at a time.
Explanation:
In what climates would you expect soil to form fastest? Why?
Answer:
Soils develop faster in warm, moist climates and slowest in cold or arid ones. Rainfall is one of the most important climate factors in soil formation.
Please mark me brainliest!
Hope this helped God bless :)
Soil formation occurs more swiftly in warm, humid areas than it does in cold or arid ones.One of the most crucial climatic variables for the formation of soil is rainfall. The breakdown of large soil particles into smaller ones is accelerated by creatures such as bacteria, plants, and animals.
What climates soil to form fastest?The rate of chemical reactions is accelerated by rising temperature, which also accelerates soil formation. Faster plant and bacterial growth in warmer climates aids in the weathering of materials and the formation of soils.
The formation of soil is another indirect effect of climate on organisms. Weathering is accelerated by precipitation and warm temperatures, which increases the amount of soil development. Rainfall increases the amount of organic matter, lowers pH, accelerates the leaching of basic ions, moves mud, etc.
Therefore, In warm, wet regions, soil development happens more quickly than in cold or arid ones. One of the most crucial climatic variables for the formation of soil is rainfall.
Learn more about climate here:
https://brainly.com/question/29166575
#SPJ1
Explain how the ESPN network has helped the sports industry grow in the past thirty years. In your explanation, you must also explain whether the industry has peaked or whether potential for growth still exists.
Answer:
Thirty years ago, the culture of American sports took a new course. An idea shouldered by a former sports communication executive, along with his son and other partners, would go on to transform the way we consume, analyze and interpret the world of athletics, and would influence international sport culture as well. While sports have always acted as a medium for those looking to escape the drudgeries of work, a way to channel negative emotions into something engaging and entertaining, ESPN presented a new opportunity for fans: an all-encompassing cable network for not only sports itself but also for the culture surrounding sports.,
Explanation:
Hope this helped!
What is the momentum of a 76–kilogram horse running at a speed of
45 kilometers/hour?
A.
2.5 × 102 kilogram·meters/second
B.
3.4 × 104 kilogram·meters/second
C.
3.4 × 103 kilogram·meters/second
D.
9.5 × 102 kilogram·meters/second
Answer:
Option D, is closest to the answer = 950.
Answer: D. 9.5x102 kilogram.meters/second
Explanation:
correct for plato
Which of the following is an example of homeostasis?
Answer:
Humans' internal body temperature is a great example of homeostasis. ...
Glucose is the most basic form of sugar, and the only type the body can use directly. ...
When bacteria or viruses that can make you ill get into your body, your lymphatic system kicks in to help maintain homeostasis.
Explanation:
Please answer correctly will give brainlist if correct
Before you kick a soccer ball you pull your leg back. For a brief moment, before you kick the ball, your leg is not moving as seen in the image below. At this point, your leg has______
Active Energy
Potential Energy
Conservation of Energy
Kinetic Energy
Answer:
Kinetic energy
4. A 65 kg woman is inside an elevator. Calculate her apparent weight (Normal Force) for the following cases:
a. The elevator moves at constant speed of 10 m/s downward (2 pts)
b. The elevator accelerates upward at a constant rate of 2.4 m/s2 (2 pts)
c. If the scale read 450 N. Find the magnitude and direction of the elevator’s acceleration. (3 pts)
Answer:
Explanation:
a ) Let her apparent weight be W₁
Net force on her = W₁ - mg
acceleration a = 0
W₁ - mg = 0
W₁ = mg = 65 x 9.8 = 637 N
b )
a = 2.4 m /s²
W₁ - mg = ma
W₁ = m(g + a )
= 65 x ( 9.8 + 2.4 )
= 793 N
c )
W₁ = 450 N
a = ?
W₁ - mg = ma
450 - 65 x 9.8 = 65 x a
65 a = - 187
a = - 2.87 m /s²
acceleration is negative therefore , it must be downwards .
The elevator was accelerating downward at a constant rate of -3.1 m/s²
Let the acceleration due to gravity (g) = 10 m/s²
a) When moving at constant speed of 10 m/s downward:
Net force = mass * g = 65 kg * 10 m/s² = 650N
b) Net force = Mass * g + mass * acceleration
Net force = (65 * 10) + (65 * 2.4) = 806 N
c) Net force = Mass * g + mass * acceleration
450 = 65 * 10 + (65*a)
65a = -200
a = -3.1 m/s²
The elevator was accelerating downward at a constant rate of -3.1 m/s²
Find out more at: https://brainly.com/question/18376691
Hellllllpppppp what happens
Answer:
u can write ur answer and submit it
its a test
Someone please makeup a hypothesis for me rq make it make sense!
With what force will a car hit a tree if the car has a mass of 3,415 kg and it is accelerating at
a rate of 5 m/s2?
Answer:
[tex]F= 17,075\ N[/tex]
Explanation:
When the car is under an accelerating force and hits a tree, the instant force received by the tree is the same force that is accelerating the car.
The accelerating force can be calculated using Newton's second law:
[tex]F=m\cdot a[/tex]
Where m is the mass of the car and a is the acceleration.
[tex]F=3,415\ kg\cdot 5\ m/s^2[/tex]
[tex]\boxed{F= 17,075\ N}[/tex]
Question 3 of 10
A 0.057 kg tennis ball and a tennis racket collide. The racket has an initial
momentum of -1.75 kg-m/s and a final momentum of -1.25 kg-m/s. The ball
has an initial momentum of 0.00684 kg-m/s. If you assume the collision is
elastic, what is the final velocity of the ball?
A. -0.50 m/s
B. -52.48 m/s
C. -2.99 m/s
d
D. -8.65 m/s
If we assume the collision to be elastic the final velocity of the ball will be -8.65 m/s, therefore the correct option is D.
What is elastic collision?It is a type of Collison for which the momentum, as well as the kinetic energy after and before the collision, is constant. there is no loss of energy in a perfectly elastic collision.
By using the law of conservation of momentum
momentum before collision = momentum after the collision
the initial momentum of rocket +initial momentum, of ball = final momentum of rocket + final momentum of the ball
By substituting the respective values
-1.75 + 0.00684 = -1.25 + m*v
-1.75 + 0.00684 = -1.25 + 0.057*v
v = -8.65 m/s
Thus, the final velocity of the ball is -8.65 m/s
Learn more about elastic collision
https://brainly.com/question/2356330
#SPJ5
A speed skater moving across frictionless ice at 8.8 m/s hits a 6.0 m -wide patch of rough ice. She slows steadily, then continues on at 5.8 m/s . What is her acceleration on the rough ice?
Recall that
v² - u² = 2 a ∆x
where u and v are initial and final velocities, respectively; a is acceleration; and ∆x is the distance traveled (because the skater moves in only one direction).
So we have
(5.8 m/s)² - (8.8 m/s)² = 2 a (6.0 m)
a = ((5.8 m/s)² - (8.8 m/s)²) / (12 m)
a = -3.65 m/s²
Which example illustrates Newton's first law?
Answer: The motion of a ball falling down through the atmosphere, or a model rocket being launched up into the atmosphere are both examples of Newton's first law. The motion of a kite when the wind changes can also be described by the first law.
Explanation:
What statements accurately describe sunspots? Check all that apply.
Sunspots are storms on the Sun's surface.
Sunspots are marked by intense magnetic activity.
Sunspots produce solar flares and hot gassy ejections.
Sunspots can affect Earth's climate.
Sunspots are cool areas where the Sun is covered by clouds.
Answer:
sunspots are storms on the Suns surface
Sunspots are marked by intense magnetic activity
Sunspots produce solar flares and hot gassy ejections.
Sunspots can affect Earth’s climate.
Explanation:
I just did this lesson
The statement that describe sunspot is Sunspots are storms on the Sun's surface.
What are sunspot?Sunspot are region of the earth that are more darker than other surfaces. They have temporary spots that are darker because the temperature of that area is cooler than other surfaces. They have a reduced temperature.
Therefore, The statement that describe sunspot is Sunspots are storms on the Sun's surface.
Learn more about sunspot below.
https://brainly.com/question/8102155
#SPJ2
The cheetah, the fastest land animal, can sprint at 30 m/s. Could the cheetah get a speeding
ticket on a highway where the speed limit is 55 mph?
Answer:
#1, cheetas can't go 30 miles per second. #2 no
Explanation:
No because animals can't get tickets.
Answer:
yes
Explanation:
it would be going 67.108 mph,
Will ice melt faster in salt, sugar or water?
Answer:
Water because the salt will just make it colder and the sugar won't do anything