Answer: c. 1.3 m/s^2
Explanation:
When he is at rest, is weight can be calculated as:
W = g*m
where:
m = mass of the man
g = gravitational acceleration = 9.8m/s^2
We know that at rest his weight is W = 824N, then we have:
824N = m*9.8m/s^2
824N/(9.8m/s^2) = m = 84.1 kg
Now, when the elevators moves up with an acceleration a, the acceleration that the man inside fells down is g + a.
Then the new weight is calculated as:
W = m*(g + a)
and we know that in this case:
W = 932N
g = 9.8m/s^2
m = 84.1 kg
Then we can find the value of a if we solve:
932N = 84.1kg*(9.8m/s^2 + a)
932N/84.1kg = 11.1 m/s^2 = 9.8m/s^2 + a
11.1 m/s^2 - 9.8m/s^2 = a = 1.3 m/s^2
The correct option is C
PLEASE HELP i’m giving 32 points!!
1.) How many grams of
potassium chloride (KCI)
can be dissolved at 80°C?
2.) At 50°C, how much potassium chlorate (KCIO3) can be dissolved in 300 grams of water?
Answer: 1 How many grams of KCl will dissolve in 1 liter of H2O at 50 °C? 5. 58.0 g of K2Cr2O7 is added to 100 g H2O at. 0 °C. With constant stirring, to what temp-. 2 34 °C? 4. How many grams of KCl will dissolve in 1 liter of H2O at 50 °C? 5. 58.0 g of ... A saturated solution of KClO3 was made with 300 g of H2O at. 34 °C.
Explanation:
What is the speed of a commercial jet which travels form New York to Los Angeles (4800) in 6 hours
Answer:
[tex]Speed = 800km}/hr[/tex]
Explanation:
Given
[tex]Distance = 4800km[/tex]
[tex]Time = 6hr[/tex]
Required
Determine the speed of the jet
The speed is calculated as:
[tex]Speed = \frac{Distance}{Time}[/tex]
Substitute 4800 km for Distance and 6hr for Time
[tex]Speed = \frac{4800km}{6hr}[/tex]
[tex]Speed = 800km}/hr[/tex]
Hence, the speed of the commercial jet is 800km/hr
A 151 kg crate is pulled along a level surface by an engine. The coefficient of kinetic friction between the crate and the surface is 0.399. How much power must the engine deliver to move the crate at a constant speed of 6.04 m/s
Answer:
3566.26 Watts
Explanation:
From the question given above, the following data were obtained:
Mass (m) of crate = 151 kg
Coefficient of kinetic friction (μ) = 0.399
Velocity (v) = 6.04 m/s
Power (P) =?
Next, we shall determine the normal reaction. This can be obtained as follow:
Mass (m) of crate = 151 kg
Acceleration due to gravity (g) = 9.8 m/s²
Normal reaction (R) = mg
Normal reaction (R) = 151 × 9.8
Normal reaction (R) = 1479.8 N
Next, we shall determine the force applied to move the crate. This can be obtained as follow:
Coefficient of kinetic friction (μ) = 0.399
Normal reaction (R) = 1479.8 N
Force (F) =?
F = μR
F = 0.399 × 1479.8
F = 590.44 N
Finally, we shall determine the power used to move the crate as follow:
Velocity (v) = 6.04 m/s
Force (F) applied = 590.44 N
Power (P) =?
P = F × v
P = 590.44 × 6.04
P = 3566.26 Watts
Therefore, the power used to move the crate is 3566.26 Watts.
Estimate the net force needed to accelerate a 1000-kg car at 3m/s/s from rest.
FILL IN THE BLANKS.
If this force acts on this car for 4 seconds, then the car will increase its speed by ————————- m/s a second each second reaching a final speed of ————————- m/s. The distance traveled during this motion is ——————- meters.
Answer:
First Blank. 30,000
Second Blank. 12,000
Third Blank. 20.0
Explanation:
PLZ HELP ASAP
With number 10 above
Answer:
P = 1500 Watt
Explanation:
Mechanical Work and Power
Mechanical work is the amount of energy transferred by a force.
Being F the magnitude of the force vector and s the distance, the work is calculated as:
W=F.s
Power is the amount of energy transferred or converted per unit of time. In the SI, the unit of power is the watt, equal to one joule per second.
The power can be calculated as:
[tex]\displaystyle P=\frac {W}{t}[/tex]
Where W is the work and t is the time.
The force to be considered is the weight of the mass of m=100 kg, [tex]g= 10\ m/s^2[/tex]:
F = 100 * 10 = 1000 N
The distance is s=3 m, thus the work done by the weight lifter is:
W = 1000 N * 3 m
W = 3000 J
Finally, the power is:
[tex]\displaystyle P=\frac {3000}{2}[/tex]
P = 1500 Watt
short essay your teacher have provided you
A car travels through a valley at constant speed, though not at constant velocity. Explain how this is possible.
Answer:
Explanation:
An object following a circular path can be covering the same distance along the circle's circumference with every passing minute, giving it a constant speed. Since a change in either speed OR direction means a change in velocity, the object's velocity is not constant.
velocity is a vector so therefore direction affects it being constant.
An object's acceleration is the rate its velocity (speed and direction) changes. Therefore, an object can accelerate even if its speed is constant - if its direction changes. If an object's velocity is constant, however, its acceleration will be zero.
Velocity is a vector so therefore direction affects it being constant.
What is velocity?When an item is moving, its velocity is the rate at which its direction is changing as seen from a certain point of view and as measured by a specific unit of time
An object following a circular path can be covering the same distance along the circle's circumference with every passing minute, giving it a constant speed. Since a change in either speed OR direction means a change in velocity, the object's velocity is not constant. An object's acceleration is the rate its velocity (speed and direction) changes. Therefore, an object can accelerate even if its speed is constant - if its direction changes. If an object's velocity is constant, however, its acceleration will be zero.
Velocity is a vector so therefore direction affects it being constant.
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g Calculate the electric potential at the center of the square with a side of 1 meter, formed by the four charged particles.
Answer:
The potential at the center of square due to four identical charges each at the corner is 5.09 q x [tex]10^1^0[/tex] Volts, where q is the charge.
Explanation:
From the question it is given that
side of square = a = 1 m
let the charge of each square is q
potential at center due to 1 charge is V = [tex]\frac{q}{4\pi \epsilon r}[/tex] , where
[tex]\epsilon[/tex] is electrical permittivity of space
r is the distance between charge and point.
since the charge is present at at the corner so the distance between charge and point is the half the length of diagonal of square.
⇒ distance between charge and point = r =[tex]\frac{a}{\sqrt{2}}[/tex] = [tex]\frac{1}{\sqrt{2} }[/tex] = 0.707 m
thus, V= [tex]\frac{q}{4\pi \epsilon r}[/tex] , on substituting the respected values of r = 0.707m and [tex]\frac{1}{4\pi \epsilon}[/tex] = 9 x [tex]10^9[/tex] we get,
V = 1.272 q x [tex]10^1^0[/tex] V
thus potential due to all 4 charges is
V = 1.272 q x [tex]10^1^0[/tex] x 4 = 5.09 q x [tex]10^1^0[/tex] Volts
Stand in a doorway so your toes and nose are against the doorway. 4. Grab a weight in each hand and hold your arms out from your body on either side of the wall. 5. Try to stand on your tip toes. What happens
Approximately, What is the value of the Hubble Constant, as measured by scientists? Hypothetically, if the value of the Hubble Constant were 700 km/s/Mpc, what would this imply about the age of our universe?
Answer:
The current value of the Hubble's constant = 73 km/sec/Mpc.
t = 71.9 trillion years will be the new age of universe if the Hubble constant = 700 km/s/Mpc
Explanation:
The current value of the Hubble's constant = 73 km/sec/Mpc. However, recent discoveries in the cosmology contradicts the idea of Hubble constant as being fixed. Some scientists are not agreeing on this value and the debate is going on.
Hubble law states that how fast universe is expanding or in other words, galaxies are expanding separating with a speed directly proportional to the distance of galaxies to the earth.
Hence,
v is directly proportional to d
where, v = apparent velocity
d = distance
if we equate velocity and distance then there comes Hubble constant.
v = [tex]H_{0}[/tex] x d
[tex]H_{0}[/tex] = 73 km/sec/Mpc
where, Mpc = Mega Parsec = 1 Mpc = 3.086 x [tex]10^{19}[/tex] km
We can use Hubble constant to tell the age of universe.
t = d/v
t = d/( [tex]H_{0}[/tex] xd)
t = 1/[tex]H_{0}[/tex]
Scientist calculated the age of universe by using Hubble constant, which is 13.4 billion years.
Now, if we hypothetically change the value of Hubble constant,
from [tex]H_{0}[/tex] = 73 km/sec/Mpc to [tex]H_{0}[/tex] = 700 km/sec/Mpc
then the age of universe will be:
t = 1/[tex]H_{0}[/tex]
first convert the units of new [tex]H_{0}[/tex] into 1/s
[tex]H_{0}[/tex] = (700) x (/3.08 x [tex]10^{19}[/tex] )
[tex]H_{0}[/tex] = 227.27 x[tex]10^{-19}[/tex] = 2.27 x [tex]10^{-21}[/tex] 1/s
So,
Age of universe will be:
t = 1/[tex]H_{0}[/tex] = 1/2.27x[tex]10^{-21}[/tex] 1/s
t = 2.27 x [tex]10^{21}[/tex] s
t = 71.9 trillion years
t = 71.9 trillion years will be the new age of universe if the Hubble constant = 700 km/s/Mpc
Given value:
Hubble Constant,
[tex]H_o = \frac{700 \ km/s}{Mpc}[/tex]We know,
[tex]Mpc = 3.086\times 10^{19} \ km[/tex]By substituting the value of "Mpc" in Hubble constant, we get
→ [tex]H_o = \frac{700}{3.086\times 10^{19}}[/tex]
[tex]= 227\times 10^{-19} \ 1/s[/tex]
[tex]= 2.27\times 10^{-21} \ 1/s[/tex]
The Hubble's time will be:
→ [tex]H_o = \frac{1}{t}[/tex]
or,
→ [tex]t = \frac{1}{H_o}[/tex]
[tex]= \frac{1}{2.27\times 10^{-21}}[/tex]
[tex]= 4.4\times 10^{20} \ seconds[/tex]
Thus the above approach is right.
Learn more about Hubble Constant here:
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( I will give a brainliest )
What must be changed, temperature or heat energy, during condensation?
Answer:
The answer is temperature lol
Explanation:
:)
A satellite of mass m orbits a moon of mass M in uniform circular motion with a constant tangential speed of v. The gravitational field strength at a distance R from the center of moon is gR. The satellite is moved to a new circular orbit that is 2R from the center of the moon. What is the gravitational field strength of the moon at this new distance
The satellite is moved to a new circular orbit that is 2R from the center of the moon, then the gravitational field strength of the moon at this new distance would be one-fourth of the initial gravitational field.
What is gravity?It can be defined as the force by which a body attracts another body toward its center as the result of the gravitational pull of one body and another.
As given in the problem A satellite of mass m orbits a moon of mass M in a uniform circular motion with a constant tangential speed of v. The gravitational field strength at a distance R from the center of the moon is gR. The satellite is moved to a new circular orbit that is 2R from the center of the moon.
The gravitational field strength is inversely proportional to the square of the distance from the center of the planet.
Thus, the gravitational field strength of the moon at this new distance would be one-fourth of the initial gravitational field.
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if a train has 1,450 kg of momentum and is traveling at 40 m/s ¿what is the mass of tren?
Help plis I have this wrong
Answer:
P=mv
1x450,200=m40
m= 36,255kg
A 3kg plastic tank that has a volume of 0.2m ^3 Is filled with liquid water . Assuming the density of water is 1000kg/m^3 determine the weight of the combined system
Answer:
The weight of the combined system is 1989.8 N.
Explanation:
The weight, W, of an object can be expressed as;
W = mg
where m is the mass of the object, and g is the acceleration due to gravity.
Weight of the combined system = weight of tank + weight of water
mass of the plastic tank = 3 kg
weight of the plastic tank = m x g
= 3 x 9.8
= 29.4 N
Weight of the plastic tank is 29.4 N
But,
density = [tex]\frac{mass}{volume}[/tex]
mass = density x volume
volume of water = 0.2 [tex]m^{3}[/tex], density of water = 1000 kg/[tex]m^{3}[/tex].
mass = 1000 x 0.2
= 200
mass of water = 200 kg
weight of water = 200 x 9.8
= 1960 N
Thus,
combined weight of the system = 29.4 + 1960
= 1989.8 N
The weight of the combined system is 1989.8 N.
4. A disobedient student dropped his Physics textbook (mass 0.1kg) from the window (15m above the ground). How fast was it going when it hit the ground?
Answer:
v= 17.15 m/s
Explanation:
mass of the book=0.1 Kg
height above ground, h= 15 m
Using conservation of energy
Potential energy is converted into kinetic energy
[tex]mgh = \frac{1}{2}mv^2[/tex]
[tex]v=\sqrt{2gh}[/tex]
[tex]v=\sqrt{2\times 9.8\times 15}[/tex]
[tex]v=\sqrt{294}[/tex]
v= 17.15 m/s
Hence, the book will hit the ground at the speed of 17.15 m/s.
Why is 1/2kx^2=gym not a linear equation
A 6.5 kg rock thrown down from a 120m high cliff with initial velocity 18 m/s down. Calculate
the following ATTENTION：using the energy/work formulae only: 3.The kinetic energy of the Rock half way down ？ 4.the speed of the Rock half way down？
5.The speed of the Rock as it hits the ground？
Answer:
See the answers below.
Explanation:
In order to solve this problem we must use the principle of energy conservation. Which tells us that the energy of a body will always be the same regardless of where it is located. For this case we have two points, point A and point B. Point A is located at the top at 120 [m] and point B is in the middle of the cliff at 60 [m].
[tex]E_{A}=E_{B}[/tex]
The important thing about this problem is to identify the types of energy at each point. Let's take the reference level of potential energy at a height of zero meters. That is, at this point the potential energy is zero.
So at point A we have potential energy and since a velocity of 18 [m/s] is printed, we additionally have kinetic energy.
[tex]E_{A}=E_{pot}+E_{kin}\\E_{A}=m*g*h+\frac{1}{2}*m*v^{2}[/tex]
At Point B the rock is still moving downward, therefore we have kinetic energy and since it is 60 [m] with respect to the reference level we have potential energy.
[tex]E_{B}=m*g*h+\frac{1}{2}*m*v^{2}[/tex]
Therefore we will have the following equation:
[tex](6.5*9.81*120)+(0.5*6.5*18^{2} )=(6.5*9.81*60)+(0.5*6.5*v_{B}^{2} )\\3.25*v_{B}^{2} =4878.9\\v_{B}=\sqrt{1501.2}\\v_{B}=38.75[m/s][/tex]
The kinetic energy can be easily calculated by means of the kinetic energy equation.
[tex]KE_{B}=\frac{1}{2} *m*v_{B}^{2}\\KE_{B}=0.5*6.5*(38.75)^{2}\\KE_{B}=4878.9[J][/tex]
In order to calculate the velocity at the bottom of the cliff where the reference level of potential energy (potential energy equal to zero) is located, we must pose the same equation, with the exception that at the new point there is only kinetic energy.
[tex]E_{A}=E_{C}\\6.5*9.81*120+(0.5*9.81*18^{2} )=0.5*6.5*v_{C}^{2} \\v_{c}^{2} =\sqrt{2843.39}\\v_{c}=53.32[m/s][/tex]
Deshaun Watson launches a football at a speed of 24.7 ms and an angle of 33° above the horizontal How far down
the football field does the football land? What is the max height the football reaches during flight?
Show work
Answer:
9.23m
Explanation:
Max height = u²sin²theta/2g
u is the speed = 34.7m/s
theta is the angle of elevation = 33°
g is the acceleration due to gravity = 9.8m/s²
Substitute into the formula
Max height = 24.7²sin²33/2(9.8)
Max height = 610.09sin²33/2(9.8)
Max height = 610.09(0.29663)/19.6
Max height = 180.97/19.6
Max Height = 9.23m
Hence the max height the football reaches during flight is 9.23m
The wavelength of a particular color of yellow light is 579 nm. The energy of this wavelength of light is
Answer:
3.44× 10⁻¹⁹Joules
Explanation:
Energy of the wavelength is expressed using the formula:
E = hc/λ
h is the Planck constant
c is the velocity of light
λ is the wavelength
Given
h = 6.63 × 10^-34 m² kg / s
c = 3×10⁸ m/s
λ = 579nm = 579 × 10⁻⁹m
λ = 5.79× 10⁻⁷m
Substitute the given values into the formula
E = hc/λ
E = (6.63 × 10⁻³⁴× 3×10⁸)/5.79× 10⁻⁷
E = 19.89× 10⁻³⁴⁺⁸/5.79× 10⁻⁷
E = 19.89× 10⁻²⁶/5.79× 10⁻⁷
E = 3.44× 10⁻²⁶⁺⁷
E = 3.44× 10⁻¹⁹Joules
Hence the energy of this wavelength of light is 3.44× 10⁻¹⁹Joules
Help! Help!
Alcohol abuse has...
A. only physiological aspects.
B. only psychological aspects.
C. physiological and psychological aspects.
Answer
I feel the answer is C because it could cause mental and physical trauma
Explanation:
Helppp!!!!!!!!!!!!?!!??
a 45 kg boy sits on a horse on a carousel 5.0 m from the center of the circle. he makes a revolution every 8.0 s.
calculate his speed.
what is centripetal force acting on the boy?
For every complete revolution the boy makes around the center of the carousel, he travels a distance of 2π (5.0 m) = 10π m, which gives a linear speed of
v = (10π m) / (8.0 s) ≈ 3.927 m/s
Then his centripetal acceleration would be
a = v ² / (5.0 m) ≈ 3.084 m/s²
so that the centripetal force exerted on him has magnitude
F = (45 kg) a ≈ 138.791 N ≈ 140 N
(rounded to 2 significant digits)
A zone plate is found to give series of images of a point source on its axis. If the strongest and the second strongest images are at distances of 0.30m and 0.06 m respectively from the zone plate (both from the same side remote from the source), calculate the distance of the source from the zone plate, principal focal length and the radius of the second zone. Assume λ = 6 x 10-7m.
A wrench is accidentally dropped at the top of an elevator shaft in a tall building. (a) How many meters does the wrench fall in 1.5s
Answer:
11.25m
Explanation:
[tex]s = ut + \frac{1}{2} a {t}^{2} \\ = 0 \times 1.5 + \frac{1}{2} \times 10 \times {1.5}^{2} \\ = 5 \times 2.25 \\ = 11.25[/tex]
An ostrich with a mass of 141 kg is running to the right with a velocity of 13m/s. Find the momentum of the ostrich. Answer in units of Kg.m/s
Answer:
1833 kg.m/sExplanation:
The momentum of an object can be found by using the formula
momentum = mass × velocity
From the question we have
momentum = 141 × 13
We have the final answer as
1833 kg.m/sHope this helps you
If a ball with a momentum of 40 kgm/s has a velocity of 2 m/s, what is its mass?
momentum (m)=40
velocity (v)=2
now,
momentum (m)=m×v
40=m×2
m=40÷2
m=20kg
What 2 factors do you need in order to calculate speed?
Answer:
Distance and time.
Explanation:
Speed=Distance/time
The two factors which we need in order to calculate the speed of an object are the distance covered by the object and the time taken to cover that distance.
What is Speed?
Speed is the rate of change of position of an object in any direction. Speed is a scalar quantity as it has only magnitude and no direction. It is measured as the ratio of the distance covered by an object to the time taken in which the distance was covered by that object.
Speed has the dimension of distance covered by the time taken. Thus, the SI unit of speed is the combination of the basic units of distance and the basic unit of Time. Thus, the SI unit of speed is meter per second (m/s).
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A woman does 236 J of work
dragging her trash can 24.4 m to
the curb, using a force of 18.9 N.
At what angle was her force
directed?
Answer:
workdone = force × distance 236J = 18.9cos(o) × 24.4236/24.4 = 18.9cos(o)(0.5117)cos^-1 = (o)59.21°You are sending waves down a spring. You send a small amplitude wave down the spring. Then you
send a large amplitude wave. The large amplitude wave is...
A.slower than the low amplitude wave
B.the same speed as the low amplitude wave
C.faster than the low amplitude wave
Answer:
a is the correct answer hope it will help you
Energy that travels in waves through matter
A mechanical wave is a disturbance in matter that transfers energy through the matter. The matter through which a mechanical wave travels is called the medium
or media in plural.
Mechanical wave are waves that travels through a medium or matter.
What are mechanical wave?A wave is a disturbance that travels or propagates from the place where it was created.
Waves transfer energy from one place to another, but they do not necessarily transfer any mass.
There are two types of waves;
mechanical wave and electromagnetic waves
electromagnetic waves are waves that that do not need any means of medium for propagation.
Examples of electromagnetic wave includes; light wave , radio wave e.t.c
Mechanical waves are waves that need medium for propagation. Example of mechanical waves includes ; sound wave , water wave e.t.c
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