Answers
Answer:
[tex]\frac{dh}{dt}=-0.4125 m/s[/tex]
Explanation:
The very first thing we can do here is to draw a sketch of the situation the problem is presenting. (See attached picture)
As you may see in the picture, we can suppose the spotlight is directly located on the ground so the light of the spotlight together with the person and the wall make two similar triangles.
In this case we need to think about the dimensions of the triangle that will change over time. We will call them:
x= distance between the spotlight and the man.
h= height of the shadow.
So we can build a relation between the height and the length of each triangle:
[tex]\frac{h}{12}=\frac{2}{x}[/tex]
the distance between the spotlight and the wall is constant, so I can directly write the 12 in my equation and the height of the man is constant as well, so I can write the 2 directly into the equation.
Next, we can solve the equation for h (since we are interested in figuring out how fast the height of the shadow is decreasing) so we get:
[tex]h=\frac{24}{x}[/tex]
So next, we need to take the derivative of the equation, since the derivative of a position function will give us the velocity at which that position is changing.
First we rewrite the equation like this:
[tex]h=24x^{-1}[/tex]
and take the derivative:
[tex]dh=-24x^{-2}dx[/tex]
we can rewrite the derivative like this:
[tex]\frac{dh}{dt}=-\frac{24}{x^{2}} \frac{dx}{dt}[/tex]
where:
dh/dt is the velocity at which the height of the shadow is decreasing (that's why our equation has a negative sign in front of it).
dx/dt is the velocity at which the value of x is increasing. In other words, how fast the man is moving away from the spotlight.
So we can go ahead and substitute:
we wish to find the velocity at which the shadow's height is decreasing when the distance between the man and the building is 4m, so in this case, x=12-4=8m
[tex]\frac{dh}{dt}=-\frac{24}{8^{2}}(1.1 m/s)[/tex]
so we get:
[tex]\frac{dh}{dt}=-0.4125 m/s[/tex]
Related Questions
Determine the absolute pressure on the bottom of a swimming pool 30.0 mm by 8.4 mm whose uniform depth is 1.9 mm .
Answers
Answer:
=101343.62N/m^2
Explanation:
absolute pressure on the bottom of a swimming pool= atmospheric pressure +( 2 ×ρ ×g)
( 2 ×ρ ×g)= guage pressure
atmospheric pressure= 101325pa
h= height= 1.9 mm = 1.9×10^-3m
ρ = density of water
= 1000kg/m^3
g= acceleration due to gravity= 9.8m/s^2
Then substitute, we have
absolute pressure on the bottom of a swimming pool= 101325+ [0.0019 ×1000 × 9.8)]
=101343.62N/m^2
Hence, the absolute pressure on the bottom of a swimming pool is =101343.62N/m^2
1. A low frequency will have a wavelength?
Answers
Answer:
There are many kinds of waves all around us. There are waves in the ocean and in lakes. Did you also know that there are also waves in the air? Sound travels through the air in waves and light is made up of waves of electromagnetic energy.
The wavelength of a wave describes how long the wave is. The distance from the "crest" (top) of one wave to the crest of the next wave is the wavelength. Alternately, we can measure from the "trough" (bottom) of one wave to the trough of the next wave and get the same value for the wavelength.
The frequency of a wave is inversely proportional to its wavelength. That means that waves with a high frequency have a short wavelength, while waves with a low frequency have a longer wavelength.
Light waves have very, very short wavelengths. Red light waves have wavelengths around 700 nanometers (nm), while blue and purple light have even shorter waves with wavelengths around 400 or 500 nm. Some radio waves, another type of electromagnetic radiation, have much longer waves than light, with wavelengths ranging from millimeters to kilometers.
Sound waves traveling through air have wavelengths from millimeters to meters. Low-pitch bass notes that humans can barely hear have huge wavelengths around 17 meters and frequencies around 20 hertz (Hz). Extremely high-pitched sounds that are on the other edge of the range that humans can hear have smaller wavelengths around 17 mm and frequencies around 20 kHz (kilohertz, or thousands of Hertz).
Explanation:
Explanation:
Hope This Helped U
Brqinliest
use particle motion to explain what happens when molten steel becomes a steel beam to be used in construction.
Answers
Explanation:
A molten steel is in a liquid phase of matter. It has no defined volume of shape at this state. The particles inside this materials in this form is randomized by they are still attached to each other.
On cooling, when the molten steel solidifies and sets into a solid steel beam, the particles take up a fixed position and forms a definite shape and this confers a definite volume on them. The randomized particles stops and forms fixed crystals about their lattice. This way, the beam can carry and support a fixed amount of load.You drop a coin off of a building and in lands flat on the ground. It hits with a pressure of 200N/m2. It has a weight of 0.1N. What is the area of the coin?
Answers
Answer:
5×10¯⁴ m².
Explanation:
From the question given above, the following data were obtained:
Pressure (P) = 200 N/m²
Weight = Force (F) = 0.1 N
Area (A) =?
Pressure, force and area are related by the following equation:
Pressure (P) = Force (F) / Area (A)
P = F / A
With the above formula, we can obtain the area of the coin as follow:
Pressure (P) = 200 N/m²
Weight = Force (F) = 0.1 N
Area (A) =?
P = F / A
200 = 0.1 / A
Cross multiply
200 × A = 0.1
Divide both side by 200
A = 0.1 / 200
A = 5×10¯⁴ m²
Thus, the area of the coin is 5×10¯⁴ m².
********************PLEASE HELP******************************************
In your own words, explain why different locations on Earth experience different seasons on any given date.
Be sure your explanation includes the following concepts:
revolution of Earth around the Sun
tilt of the Earth
angle insolation
focus/spread of Sun’s rays
temperature
You must also explain how you know that seasons are not caused by the Earth’s slight changes in distance from the Sun throughout the year.
Answers
In east Asia monsoons happen a lot
Hurricanes happen in the Atlantic
PLEASE HELP ASAP
ILL GIVE BRAINLIEST
2. What are three crucial pieces of evidence that supports the claim for the Big Bang theory. Include a piece of evidence that relates each of the following:
a. Light spectra
b. Motion of distant galaxies
c. Composition of matter in the universe
3. Explain how or why each piece of evidence supports the claim made in Big Bang theory.
Answers
Answer:
The evidence that the universe is expanding comes with something called the red-shift of light. Light travels to Earth from other galaxies. As the light from that galaxy gets closer to Earth, the distance between Earth and the galaxy increases, which causes the wavelength of that light to get longer. Distant galaxies are getting further away hinting at a point of origin. The composition of all observed matter in this universe points at a common origin point for all matter in the universe.
The three crucial evidences that supported the Big Bang theory are the CMB or cosmic microwave background, the expanding universe, the abundance of elements in the universe.
What is Big Bang theory ?Big Bang theory is one of the important theory scientists used in earliest to describe the origin of universe and the phenomenon of evolution.
Here,
2. The Big Bang theory described the origin of universe as an expansion from an atmosphere of high density and extreme temperature which lead to a huge explosion of matter known as the 'Big Bang' and thus creation of the universe.
The three crucial evidences that supported the Big Bang theory are:
The CMB or cosmic microwave background, the expanding universe, the abundance of elements in the universe.
3.(a) Light spectra was an important factor that supported the Big Bang theory mainly by the phenomenon called Doppler shift. Doppler shift occurs when stars move away, they get shifted to longer wavelength. This phenomenon is called red-shift or Doppler's Red shift. This was applicable in the case of Big Bang theory such that the theory claimed that, as a result of explosion which is the Big Bang, the material particles move away. This was similar to the red shift.
(b) The motion of distant galaxies was an evidence of the expansion of universe and soo the Big Bang theory. It was explained in such a way that, as the galaxies move away from us, it shows the more expansion of universe and the time duration since the origin of universe.
(c) The composition of matter in the universe was an important evidence that supported the Big Bang theory. The composition of universe that there is high abundance of hydrogen and helium in the atmosphere was claimed by the Big Bang theory.
Hence,
The three crucial evidences that supported the Big Bang theory are the CMB or cosmic microwave background, the expanding universe, the abundance of elements in the universe.
To learn more about Big Bang theory, click:
https://brainly.com/question/1160650
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A different bullet has a mass of 0.09 kg. Starting from rest, after its gun's trigger is pulled, a constant force acts on the bullet for the next 0.025 seconds until the bullet leaves the barrel of the gun with a speed of 1,346 m/s.
What force acts on this bullet?
Answers
The force acts on this bullet : 4.8456 N
Further explanationGiven
m=0.09 kg
Δt=0.025 s
vo=0(from rest)
vt=1.346 m/s
Required
Force
Solution
Impulse is a change in momentum
I=ΔP
F.Δt=m(vt-vo)
Input the value
F x 0.025 = 0.09(1.346-0)
F=4.8456 N
What are your thoughts about Russia getting banned from the 2020 Olympics and 2022 World cup?
Answers
A 1,000 kg truck initially had a velocity of 9 m/s. A force acts on it for a duration of time. After that force, the truck now has a velocity of 17 m/s. What is the impulse that the truck experienced?
Answers
Answer:
8000Ns
Explanation:
Given parameters:
Mass of the truck = 1000kg
Initial velocity = 9m/s
Final velocity = 17m/s
Unknown:
Impulse = ?
Solution:
The impulse experienced by the truck is the the change in momentum of the body.
Impulse = Ft
Momentum = m(v - u)
Ft = m( v - u )
F is the force
t is the time
m is the mass
v is the final velocity
u is the initial velocity
Impulse = 1000(17 - 9) = 8000Ns
A 0.41kg football that is initially at rest acquires a velocity of 35m/s when it is kicked. If the kicker's boot remains in contact with the ball for 0.08s, what is the average force of the kick?
Answers
Answer:
F = 318.88[N]
Explanation:
This problem can be solved by the principle of momentum conservation, which tells us that momentum is preserved before and after kicking the ball.
In this way, we can construct the following equation.
[tex]F*t=m*v[/tex]
where:
F = force [N]
t = time = 0.08 [s]
m = mass = 0.41 [kg]
v = velocity [m/s]
[tex]F*0.045=0.41*35\\F=318.88[N][/tex]
Essential Questions: What does the particle theory tell us about the nature of matter? How does
each state of matter behave?
Answers
sowwie :( i need points
Explanation:
A ball falls through the air at terminal velocity. Which of the following are forces that should be included in a free body
diagram? (select all that apply)
air resistance
force of motion
gravity
force of fall
Answers
Answer:
air resistance and gravity.
Explanation:
When the ball is falling down at terminal velocity, the velocity is constant.
This means that the net force acting on the ball will be zero (there is no acceleration)
In this situation, there are only two forces that can act on the ball.
The gravitational force, that pulls the ball down.
The air resistance which opposes to the movement of the ball and increases in magnitude as the velocity of the ball increases.
Then there is a point where the velocity of the ball is such that the air resistance is equal in magnitude to the acceleration, and then the net force becomes zero.
Then the two forces that need to be included in this diagram are the air resistance and gravity.
how are hydrosphere, atmosphere, Biosphere, and Biosphere connected to one another
Answers
Explanation:
Such spheres are intimately connected. Many animals (biosphere), for example, migrate through to the sky, while groundwater (hydrosphere) also flows through the ground (lithosphere). The domains are actually so closely related that a shift in one globe always results in a shift in one or both of some other spheres.
A 1.5kg object moving with a speed of 2.5m/s strikes a wall and the ball rebounds with a speed of 1.5m/s. The ball is in contact with the wall for 0.045s. What is the magnitude of the average force exerted on the ball by the wall?
Answers
Answer:
F = 133.33[N]
Explanation:
This problem can be solved by the principle of momentum conservation, which tells us that momentum is preserved before and after the bounce of the ball on the wall.
In such a way that the movement towards the wall we will take it with a positive sign, and the force of the rebound to the left as negative. The movement to the left will be taken as a negative sign.
[tex]m_{1}*v_{1}-F*t=-m_{1}*v_{2}[/tex]
where:
m₁ = mass of the object = 1.5 [kg]
v₁ = velocity of the ball before hitting the wall = 2.5 [m/s]
F = average force [N]
t = time contact = 0.045 [s]
v₂ = velocity of the ball after hitting the wall = 1.5 [m/s]
Now replacing:
[tex](1.5*2.5)-F*0.045=-(1.5*1.5)\\3.75+2.25=F*0.045\\F=6/0.045\\F=133.33[N][/tex]
(BRAINLIEST)
Which is an example of the force of attraction between two objects that have mass?
Magnetism
Gravity
Solar energy
Electricity
(BRAINLIEST)
Answers
Answer:
Gravity
because it's factorised by mass of a body.
For other forces, they deal with charges of negligible mass and weights
Answer:
Gravity
Explanation:
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?
Answers
Answer:
workdone = force × distance 236J = 18.9cos(o) × 24.4236/24.4 = 18.9cos(o)(0.5117)cos^-1 = (o)59.21°A 4 kg bowling bowl is sitting on a table 1 meter off the ground. How much potential energy does it have?
Answers
Answer:
[tex]\huge\boxed{\sf P.E. = 39.2\ Joules}[/tex]
Explanation:
Given Data:
Mass = m = 4 kg
Acceleration due to gravity = g = 9.8 m/s²
Height = h = 1 m
Required:
Potential Energy = P.E. = ?
Formula:
P.E. = mgh
Solution:
P.E. = (4)(9.8)(1)
P.E. = 39.2 Joules
[tex]\rule[225]{225}{2}[/tex]
Hope this helped!
~AH1807what causes sound to have low pitch
A.Sound Wave with high frequency.
B.sound wave with low frequency.
C.sound wave with large amplitude
D.sound wave with small amplitude
Answers
You throw a baseball a distance of 20 meters. Is it work or not work?
Answers
How far will a 10N force pull a car if the work done is 20J?
Answers
How can the relationship between atomic number and the number of protons be described?
Answers
Answer:
It's the number of protons in the nucleus of the atom
An inductor with an inductance of .5 henrys (H) is to be connected to a 60 Hz circuit. What will the inductive reactance (X L) be
Answers
Answer:
1885.2 ohms
Explanation:
Step one:
given data
L=5H
f=60Hz
Required
The inductive reactance of the inductor
Step two:
Applying the expression
XL= 2πfL
substitute
XL=2*3.142*60*5
XL=1885.2 ohms
Two hockey pucks with mass 0.1 kg slide across the ice and collide. Before
the collision, puck 1 is going 15 m/s to the east and puck 2 is going 12 m/s to
the west. After the collision, puck 2 is going 15 m/s to the east. What is the
velocity of puck 1?
Answers
Answer:
Puck 1 = 12 m/s
Explanation:
Conservation of energy
KE_1a + KE_2a = KE_1b + KE_2b
(1/2)(0.1kg)(15m/s)^2 + (1/2)(0.1kg)(12m/s)^2 = (1/2)(0.1kg)(V)^2 + (1/2)(0.1kg)(15m/s)^2
V = 12m/s
Answer:
12 m/s west
Explanation:
just did it
A 3.6kg cat is laying on a tree branch, 3 meters above the ground. What is the cat’s potential energy?
Answers
Answer:
E = 105.84 J
Explanation:
Given that,
Mass of cat, m = 3.6 kg
It is laying 3 meters above the ground.
We need to find the cat's potential energy. The formula for the potential energy of an object is given by :
E = mgh
Substituting all the values,
E = 3.6 kg × 9.8 m/s²×3 m
E = 105.84 J
So, the cat's potential energy is 105.84 J.
Need help y’all ASAP please...physics
Answers
Answer:
t = 3/8 seconds
Explanation:
h=-16t^2 - 10t+6
h= 0 when it hits the ground
0=-16t^2 - 10t+6
factor out a -2
0= -2(8t^2 +5t -3)
divide by -2
0 = (8t^2 +5t -3)
factor
0=(8t-3) (t+1)
using the zero product property
8t-3 = 0 t+1 =0
8t = 3 t= -1
t = 3/8 t= -1
t cannot be negative ( no negative time)
t = 3/8 seconds
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?
Answers
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:
https://brainly.com/question/13691927?
1. Calculate the momentum of a 1.0 kg object moving with a velocity of +20 m/s.
2. What is the velocity of an object that has a momentum of -30 kg m/s and a mass of 3.0 kg?
3. Two objects have equal momentum but one has four times the mass of the other. What is the relationship between
their velocities?
4. Which answer below shows the correct units for momentum?
A. kg m/s
B. kg m/s?
C. kg m/s
D. kg s/m
5. Two bowling balls each have a mass of 4.0 kg
The red Bar is moving east 2.0 m/s. The blue ball is moving west at 1.0 m/s. Calculate the total momentum of the system.
Answers
Answer:
1)1*20=20
2)-30/3=- -10
3)velocity of the object 1=v1=4*V2
4) kg m/ s
5) momentum of the system= 12 kg m/ s
in 1-2 complete sentences define "opportunity cost " in your own words
Answers
Answer:
Here you go, hope this helps! :)
Explanation:
Opportunity cost is the value of the next best thing you give up whenever you make a decision. It is "the loss of potential gain from other alternatives when one alternative is chosen". ... For example, opportunity cost is how much leisure time we give up to work.
A woman holds a frozen smoothie in her hand on a warm
day.
Which photo shows the direction of thermal energy transfer?
O A.↕️
B
C ⬆️
D⬇️
Answers
Answer:
C
Explanation:
The thermal energy from her hand will go up into the smoothie.
Answer:
C bois
Explanation:
The electron has the positron as its antiparticle.
A True
B False
