We are given:
the initial height of the object (h) = 100 m
initial velocity (u) = 0 m/s
we will let the value of g = 10 m/s/s
Speed of the object just before hitting the ground:
From the third equation of motion:
v² - u² = 2ah (where v is the final velocity)
replacing the variables, we get:
v² - (0)² = 2(10)(100)
v² = 2000
v = 10√20 = 44.7 m/s
Therefore, the speed of the object just before hitting the ground is 44.7 m/s
Problem 9.23 A uniform-density 8 kg disk of radius 0.21 m is mounted on a nearly frictionless axle. Initially it is not spinning. A string is wrapped tightly around the disk, and you pull on the string with a constant force of 36 N through a distance of 0.9 m. Now what is the angular speed?
Answer:
4.63rad/s
Explanation:
The centripetal force is expressed as;
F = mv²/r
M is the mass of the disk = 8kg
v is the linear speed = wr
r is the radius = 0.21m
Force = 36N
Write the force in term of the angular velocity
F = m(wr)²/r
F = mw²r²/r
F = mw²r
36 = 8w²(0.21)
36 = 1.68w²
w² = 36/1.68
w² = 21.43
w = √21.43
w = 4.63rad/s
Hence the angular speed is now 4.63rad/s
which equation should be used to find speed
Answer:
The formula for speed is speed = distance ÷ time. To work out what the units are for speed, you need to know the units for distance and time. In this example, distance is in metres (m) and time is in seconds (s), so the units will be in metres per second (m/s).
The bandgap of InP semiconductor laser is 1.0 eV. The effective mass of the valence band is ½ of the effective mass of the conduction band. Assuming that electron hole recombination transition occurs at 0.03 eV above the bandgap, calculate the wavelength of this transition.
Answer: the wavelength of this transition is 1.2039 um
Explanation:
Given that;
the energy level between the transitioning energy gap Eg = 1.0 + 0.03 = 1.03 eV
we know that λ = 1.24 / Eg
so we substitute our Eg into the above equation
λ = 1.24 / 1.03
λ = 1.2039 um
therefore the wavelength of this transition is 1.2039 um
A person following a liberal ideology would likely approve of
At a certain instant, a proton is moving in the positive x direction through a magnetic field in the negative z direction. What is the direction of the magnetic force exerted on the proton
Answer: positive y direction
Explanation:
we know that direction of velocity is in +x direction
now the magnetic force is in negative z direction
therefore the magnetic force , F = q × ( v × B)
F = ( i × [ - k ] ) direction
F = j direction
so the direction of the magnetic force on the proton is positive y direction.
A particle is moved along the x-axis by a force that measures 10/(1+x)^2 pounds at a point x feet from the origin. Find the work (in ft-lb) done in moving the particle from the origin to a distance of 9 feet.
Answer:
9 ft*lb
Explanation:
super simple but you just have to understand that the integral is going with the curve
work = integral a to b of f(x)dx = integral 0 to 9 of 10/(1+x)^2dx = 9ft*lb
A vector of components (−23, −22) is multiplied by the scalar value of −6. What is the magnitude and direction of the resultant vector?
Answer:
(1,)
Explanation:
Answer:
magnitude: 21.6; direction: 33.7°
Explanation:
How could you separate a mixture of rocks and sand?
A "lovesick" individual wants to throw a bag of candy and love notes into the open window of their significant other’s bedroom 10.0 m above. Assuming it just reaches the window, they throw the gift at 60.0o to the ground: At what velocity should they throw the bag? How far from the house are they standing when they throw the bag? (Answer: A. 16.2m/s B. 11.5m)
Answer:
Explanation:
Let the velocity be v .
vertical component of the velocity = v sin 60 = √3 v /2
it reaches maximum height of 10 m .
v² = 2 gh
( √3 v/2 )² = 2 x 9.8 x 10
3 v² = 196 x 4
v² = 65.33 x 4
v = 16.2 m /s
Let time taken to reach height of 10 m
v = u - gt
v sin 60 = 9.8 t
16.2 x √3 /2 = 9.8 t
t = 1.43 s
horizontal distance covered = v cos 60 x t
16.2 x .5 x 1.43 = 11 .5 m
If we assume their arms are each 0.90 m long and their individual masses are 65.0 kg , how hard are they pulling on one another
Complete Question
On an ice rink two skaters of equal mass grab hands and spin in a mutual circle once every 2.7 s .
If we assume their arms are each 0.90 m long and their individual masses are 65.0 kg , how hard are they pulling on one another?
Answer:
The force is [tex]F = 316.8 \ N[/tex]
Explanation:
From the question we are told that
The period is T = 2.7 s
The radius of the circle formed by their arms is r = 0.90 m
Their individual mass is [tex]m = 65.0 \ kg[/tex]
Generally their angular velocity is mathematically represented as
[tex]w = \frac{2 \pi}{T}[/tex]
=> [tex]w = \frac{2 * 3.142 }{2.7}[/tex]
=> [tex]w =2.327 \ rad/ s [/tex]
Generally the pulling force is mathematically represented as
[tex]F = m * w ^2 * r[/tex]
=> [tex]F = 65 * 2.327^2 * 0.90[/tex]
=> [tex]F = 316.8 \ N[/tex]
True.or false A railroad track runs southwest to northeast.
Answer:
ns for high-speed rail in the United States date back to the High Speed Ground Transportation Act of 1965. Various state and federal proposals have followed. Despite being one of the world's first countries to get high-speed trains (the Metroliner service in 1969), it failed to spread. Definitions of what constitutes high-speed rail vary, including a range of speeds over 110 mph (180 km/h) and dedicated rail lines. Inter-city railwith top speeds between 90 and 125 mph (140 and 200 km/h) is sometimes referred to in the United States as higher-speed rail.[1]
Amtrak's Acela Express (reaching 150 mph, 240 km/h), Silver Star, Northeast Regional, Keystone Service, Vermonter and certain MARC Penn Line express trains (all five reaching 125 mph, 201 km/h) are the only high-speed services in the country.
As of 2020, the California High-Speed Rail Authority is working on the California High-Speed Rail project and construction is under way on sections traversing the Central Valley. The Central Valley section is planned to open in 2029 and Phase I is planned for completion in 2031.[2]
Contents
1 Definitions in American context
2 History
2.1 Faster inter-city trains: 1920–1941
2.2 Post-war period: 1945–1960
2.3 First attempts: 1960–1992
2.4 Renewed interest: 1993–2008
2.5 Plans for 2008–2013
3 Current state and regional efforts
3.1 The Northeast
3.1.1 Northeast Corridor: Next Generation High-Speed Rail
3.1.1.1 Proposed routes
3.1.2 Northeast Maglev proposal
3.1.3 New Jersey–New York City upgrades
3.1.4 New York
3.1.5 Pennsylvania
3.2 Western States
3.2.1 California
3.2.2 Pacific Northwest
3.2.3 Arizona
3.3 Mid-Atlantic and the South
3.3.1 Florida
3.3.2 Southeast
3.3.3 Texas
3.4 Midwest
3.4.1 Illinois and the Midwest
3.5 The Southwest
4 Federal high-speed rail initiatives
4.1 American Recovery and Reinvestment Act of 2009
4.1.1 Strategic plan
4.2 2009 federal grant funding
4.3 2010 allocation
4.3.1 Cancellation of funds for Wisconsin, Ohio, and Florida
4.4 2011 and 2012 proposals and rejections of funding
5 See also
6 Notes
7 Further reading
8 External links
Explanation:
how much min the basketball 1 player play
Answer:
A professional basketball game depends on the association presiding over the game. An NBA game lasts for 48 minutes whereas FIBA games take 40 minutes. The total time taken to play for any specialized game is over 2 hours 15 minutes. The time includes the time disruptions like fouls, timeouts, and breaks.
I hope it helps you...
How long would it take you to walk 3,962 km from New York to Los
Angeles?
Answer:
913 hours ur welcome :)
Notice that the electromagnet in the virtual simulation is made up of a battery and a wire. What item could you add to the electromagnet to make it even stronger?
Answer:
Explanation:
Have y’all seen steeleflag19 at all on here?
The acceleration of the spacecraft in which the Apollo astronauts took off from the moon was 3.4 m/s2 m / s 2 . On the moon, g g = 1.6 m/s2 m / s 2 . what's the apparent weight
Complete Question
The acceleration of the spacecraft in which the Apollo astronauts took off from the moon was 3.4 m/s2. On the moon, g = 1.6 m/s2. What was the apparent weight of a 75 kg astronaut during takeoff?
Answer:
The value is [tex]N = 375 \ N[/tex]
Explanation:
From the question we are told that
The acceleration is [tex]a = 3.4 \ m/s^2[/tex]
The acceleration due to gravity in the moon is [tex]g = 1.6 m/s^2[/tex]
The mass of the astronaut is [tex]m = 75 \ kg[/tex]
Generally the apparent weight is mathematically represented as
[tex]W = ma + mg[/tex]
=> [tex]W = 3.4 * 75 + 1.6 * 75[/tex]
=> [tex]W = 375 \ N[/tex]
What measurements would you make (assuming you have the money, time, & equipment) to determine a star’s surface temperature? Explain your answer.
Answer:
use special filters on the telescope
Explanation:
Assuming you have access to a very high-grade telescope you would need to use special filters on the telescope that allows you to view the star's color spectrum. The color spectrum represents different levels of heat that a star is generating. This spectrum ranges from red to blue. Therefore in order to calculate the surface temperature, you would need to apply both a blue and red filter onto the telescope. Once you have these measurements you would need to compare them in order to pinpoint the correct variation of color which would give a close enough estimate of the surface temperature of the star.
A car starts from rest and accelerates for 7.2 s with an acceleration of 1.4 m/s2. How far does it travel? Answer in units of m.
Answer:
xn = 36.28 [m]
Explanation:
To solve this problem we must use the following equation of kinematics, which is ideal for a body that moves with constant acceleration.
[tex]x=x_{0}+(v_{o} *t)+(\frac{1}{2} )*a*t^{2}[/tex]
where:
x - xo = displacement of the car [m]
Vo = initial velocity = 0
t = time = 7.2 [s]
a = acceleration = 1.4 [m/s^2]
The initial velocity is zero, as the car begins its movement from rest.
xn = (x - xo), Now replacing
xn = (0*7.2) + 0.5*1.4*(7.2^2)
xn = 36.28 [m]
Write a function to accept a vector of masses (m) from the user and gives the corresponding energy to them. Energy vector is the output of the program. Constant c is the speed of light which is 2.9979 x 108 m/s inside the function.
Answer:
Written in Python
def energyvector(mass):
c = 2.9979 * 10**8
energy = mass * c ** 2
print(round(energy,2))
Explanation:
This line defines the function
def energyvector(mass):
This line initializes the speed of light
c = 2.9979 * 10**8
This line calculates the corresponding energy
energy = mass * c ** 2
This line prints the calculated energy
print(round(energy,2))
2. If a car is accelerating under a net force of 3674 N, what force must the
brakes exert to cause the car to have constant velocity?*
Answer:
I don't do physics but I think the answer would be -3674
Explanation:
Newton's 2 law of motion
It took 50 joules to push a chair 5 meters across the floor. With what force was the chair pushed?
Answer:
The chair was pushed with 10 N.
Explanation:
The chair was pushed with 50 Joules.
Work = Force * Distance
50 J = F * 5m
F = 50 / 5 = 10N
The chair was pushed with 10 N.
The chair was pushed with 10 N force.
What is Work done?Work is defined as the measure of energy transfer that occurs when an object is moved over a distance by an external force, at least part of which is applied in the direction of displacement.
If the force is constant then work can be calculated by multiplying the length of the path by the component of the force acting along the path, which is expressed mathematically as work W equal to the force f over a distance d, or W = fd.
So, for above given information,
Work done= 50 joules
Distance covered by the chair = 5m
Then, Force= W/d
=50/5= 10N
Thus, the chair was pushed with 10 N force.
Learn more about Work done, here:
https://brainly.com/question/13662169
#SPJ2
Define reflection of sound?
A balloon is launched straight upward from the edge of a 40 m high cliff with a velocity of 30
m/s. The balloon goes up and barely misses the edge of the cliff on the way down and hits the
ground below.
A.) Determine the overall hang time of the balloon.
B.) How high did the balloon travel above the cliff?
C.) Determine the velocity of the balloon at t = 3 s.
D.) Determine the acceleration of the balloon at t = 3 s.
Answer:
A) t = 7.25 sec
B) 45.92 m above the cliff and 85.92 m counting from ground level
C) about 0.6 m/s
D) The only acceleration is always that of gravity : 9.8 m/s^2
Explanation:
The kinematic equation for the position as a function of time is:
y = 40 + 30 * t - (g/2) t^2
The total time the balloon was in the air is calculated for when the final position is y = 0 (when it touches the ground), that is:
0 = 40 + 30 * t - (g/2) t^2
0 = 40 +30 t - 4.9 t^2
which can be solved for "t" using the quadratic formula, and which renders two different times "t", of which we pick the positive answer: t = 7.25 sec.
For the maximum height, we estimate the time it takes for the balloon to reach the maximum height at which the velocity is zero (changes direction of motion):
vf = vi - g * t
0 = 30 - 9.8 * t
t = 30 / 9.8 = 3.06 seconds
Now we use this value in our position equation and get:
ymax = 40 + 30 (3.06) - 4.9 (3.06)^2
ymax = 85.92 m (from ground level
Therefore, from the cliff (that is at 40 m height) the height is 85.92 - 40 = 45.92 m.
The velocity of the balloon at t = 3 seconds can be calculated with the velocity expression we have been using:
v(t) = vi - g * t
v(3) = 30 - 9.8 (3) = 0.6 m/s
The only acceleration acting on the balloon is always the acceleration due to gravity (g = 9.8 m/s^2)
1. The uniform seesaw is balanced at its center of mass. The smaller boy on the right has a mass of m = 40.0 kg. What is the mass of his friend?
Answer:
Explanation:
Find the complete question attached
Using the principle of moment
Clockwise moment = Anticlockwise moment
AntiClockwise moment = M × 2.0
ACW moment = 2M
Clockwise moment = 40×4
Clockwise moment = 160kgcm
Equate both expression and calculate M
2M = 160
M = 160/2
M = 80kg
Hence the mass of his friend is 80kg
A tightly wound solenoid is 15 cm long, has 350 turns, and carries a current of 4.0 A. If you ignore end effects, you will find that the value of app at the center of the solenoid when there is no core is approximately
Answer:
The magnetic field at the center of the solenoid is approximately 0.0117 T
Explanation:
Given;
length of the solenoid, L = 15 cm = 0.15 m
number of turns of the solenoid, N = 350 turns
current in the solenoid, I = 4.0 A
The magnetic field at the center of the solenoid is given by;
[tex]B = \mu_o (\frac{N}{L} )I\\\\B = (4 \pi *10^{-7})(\frac{350}{0.15} )(4.0)\\\\B = 0.0117 \ T[/tex]
Therefore, the magnetic field at the center of the solenoid is approximately 0.0117 T.
A jet plane lands with a speed of 100 m/s and can
accelerate at a maximum rate of 5.00 m/s2 as it comes to
rest. (a) From the instant the plane touches the runway,
what is the minimum time needed before it can come to
rest? (b) Can this plane land on a small tropical island
airport where the runway is 0.800 km long?
Answer:
a) t = 20 [s]
b) Can't land
Explanation:
To solve this problem we must use kinematics equations, it is of great importance to note that when the plane lands it slows down until it reaches rest, ie the final speed will be zero.
a)
[tex]v_{f}=v_{i}-(a*t)[/tex]
where:
Vf = final velocity = 0
Vi = initial velocity = 100 [m/s]
a = desacceleration = 5 [m/s^2]
t = time [s]
Note: the negative sign of the equation means that the aircraft slows down as it stops.
0 = 100 - 5*t
5*t = 100
t = 20 [s]
b)
Now we can find the distance using the following kinematics equation.
[tex]x -x_{o}=(v_{o}*t)+\frac{1}{2}*a*t^{2}[/tex]
x - xo = distance [m]
x -xo = (0*20) + (0.5*5*20^2)
x - xo = 1000 [m]
1000 [m] = 1 [km]
And the runaway is 0.8 [km], therefore the jetplane needs 1 [km] to land. So the jetpalne can't land
a Venus fly trap is an......... plant.
Answer:
A Venus flytrap is a perennial carnivorous plant.
I hope it helps
plant that eats meat
Someone help
Match the definition to the term.
1.
the noun that follows the verb and answers the questions
whom or what
linking verb
2. a word that expresses action
sentence
3. who or what the sentence is about
predicate noun
4.
a noun that indicates to or for whom or what something is
done
predicate adjective
5. follows a linking verb and renames the subject
direct object
subject
6. follows a linking verb and describes a subject
verb that joins a subject and a predicate noun or predicate
7.
adjective
indirect object
8. expresses a complete thought
verb
Answer:
Explanation:
No 1 is linked to the option provided at no 5.
A direct object is the noun that follows the verb and answers the question.
No 2 is linked to the option provided at no 8.
A verb is a word that expresses action.
No 3 is linked to the option provided at no 5.
The subject is what or whom the sentence is about.
No 5 is linked to the option provided at no 3.
A predicate noun follows a linking verb, and renames the subject.
No 6 is linked to the option provided at no 4.
A predicate adjective follows a linking verb, and describes a subject.
No 7 is linked to the option provided at no 1.
A linking verb joins a subject and a predicate.
No 8 is linked to the option provided at no 2.
A sentence expresses a complete thought....
Answer:
predicate noun: follows a linking verb and describes a subject
verb: a word that expresses action
direct object: a noun that indicates to or for whom or what something is done
sentence: expresses a complete thought
predicate adjective: verb that joins a subject and a predicate noun or predicate adjective
subject: who or what the sentence is about
indirect object: follows a linking verb and renames the subject
linking verb: the noun that follows the verb and answers the questions whom or what
Hope this helps!
Correct me if I'm wrong:)
please help asap
You jog for 55 minutes and reach a park that is 4.8 km away. What was your speed?
Answer: 59.8 or 299/5- 55 x 4.8=264
Explanation:
Or if you wish to multiply it then the answer is above with the addition version.
Hope this helped :)
R=(4.7)^2+(6.6)^2-2.(4.7)+(6.6).(180-45)
Answer:
I have no clue what this means or what the answer is i am just trying to get my points up so i can ask questions
Explanation:
i am going to put something here so it looks like an explanation so yeah this has no meaning whatsoever i am very sorry that i am not able to give you the answer try looking the answer up im very very very very sorry :(
how are s waves and p waves simuliar?
A.they shake the ground
B.they travel through liquids
C. they arrive at the same time
D.they shake the ground from side to side
Answer:
A
Explanation:
hope this helps