Answer:
a) Eg = 3,060.72 j
b) Ek = 2,080 j
c) Etotal = 5,140.72 j
d) Eg = 5,140.2 j
Ek = 0 j
Etotal = 5,140.2 j
Explanation:
The given parameters of the person riding the skateboard are;
The mass of the person, m = 65 kg
The height of the person (above ground level), h = 4.8 m
The speed at which the person is traveling, v = 8.0 m/s
a) The gravitational potential energy, Eg = m·g·h
Where;
m = The mass of the object at the given height = 65 kg
g = The acceleration due to gravity, g ≈ 9.81 m/s²
h = The height by which the object is elevated = 4.8 m
∴ Eg = 65 kg × 9.81 m/s² × 4.8 m = 3,060.72 joules
The gravitational potential energy, Eg = 3,060.72 J
b) The kinetic energy, Ek, is given as follows;
Ek = 1/2·m·v²
Where;
v = The velocity of the object = 8.0 m/s
∴ Ek = 1/2 × 65 kg × (8.0 m/s)² = 2,080 joules
The kinetic energy, Ek = 2,080 J
c) The total mechanical energy, Etotal = Eg + Ek
∴ Etotal = 3,060.72 j + 2,080 j = 5,140.72 J
The kinetic energy, Ek = 5,140.72 J
d) If the ramp had a total height of 8.0 m, we have;
At the 8.0 m height
Etotal = Eg(max), Ek = 0 j
With the given values, we get;
Eg(max) = 65 kg × 9.81 m/s² × 8 m = 5,101.2 joules = Etotal
Eg(max) = 5,101.2 j
Etotal = 5,101.2 j
Ek = 0 j
However, using only the values in the question with the assumption that all things being equal, we have;
Etotal = Constant = 5,140.72 j
Eg a the max height, 8.0 m = Eg(max) = Etotal = 5,140.2 j
Ek = 0 j
A dog sits on a flat surface. If the dog has a mass of 13 kg, what is the normal force acting on it?
85 N
13 N
127 N
41 N
Answer:
127
Explanation:
f(n)=mg
(13)*(9.81)
127.4N
8. An electric force F exists between two objects, both having thecharge, q. If the charge on one object is doubled to 2q, the force
between the objects becomes
A. 1/4 F
B. 1/2 F
C. 2F
D. 4F
Write your question here (Keep it simple and clear to get the best answer) a car accelerates uniformly from an initial velocity of 10m/s at 2m/s squre for 4s.What is the average velocity
Answer:
Average velocity = 18 m/s
Explanation:
Given the following data;
Initial velocity = 10m/s
Acceleration = 2m/s²
Time = 4 seconds
To find the average velocity, we would use the first equation of motion;
[tex] V = U + at[/tex]
Where;
V is the final velocity.
U is the initial velocity.
a is the acceleration.
t is the time measured in seconds.
Substituting into the equation, we have;
V = u + at
V = 10 + 2*4
V = 10 + 8
V = 18 m/s
What kind of energy does an electromagnet use to pick up metallic objects?
Answer:
Magnetic energy is used by an electromagnet to pick up metallic objects
Explanation:
An electromagnet generates its own magnetic field in presence of electric current.
As an electric current is induced in an electromagnet , it magnetic dipole arrange themselves in order to behave as a magnet and hence generate magnetic field with a proper north and south. This leads to attraction of metallic object.
Hence, it can be said that Magnetic energy is used by an electromagnet to pick up metallic objects
The loudness, L, measured in decibels (Db), of a sound intensity, I, measured in watts per square meter, is defined as , where and is the least intense sound a human ear can hear. Jessica is listening to soft music at a sound intensity level of 10-9 on her computer while she does her homework. Braylee is completing her homework while listening to very loud music at a sound intensity level of 10-3 on her headphones. How many times louder is Braylee’s music than Jessica’s? times louder 3 times louder 30 times louder 90 times louder
Answer:
3 times louder
Explanation:
The Loudness in decibel Db L = 10㏒(I/I₀) where I = sound intensity level and I₀ = threshold of hearing = 10⁻¹² W/m².
Now, for Jessica, I₁ = sound intensity level of Jessica's music = 10⁻⁹
and I₂ = sound intensity level of Braylee's music = 10⁻³
So, substituting the variables into the equation, we have
L₁ = 10㏒(I₁/I₀)
L₁ = 10㏒(10⁻⁹/10⁻¹²)
L₁ = 10㏒(10³)
L₁ = 3 × 10㏒10
L₁ = 30㏒10
L₁ = 30 dB
Now, for Braylee, I₂ = sound intensity level of Braylee's music = 10⁻³
So, substituting the variables into the equation, we have
L₂ = 10㏒(I₁/I₀)
L₂ = 10㏒(10⁻³/10⁻¹²)
L₂ = 10㏒(10⁹)
L₂ = 9 × 10㏒10
L₂ =90㏒10
L₂ = 90 dB
So, the number of times Braylee's music is louder than Jessica's music is L₂/L₁ = 90 dB/30 dB = 3
So, Braylee's music is 3 times louder than Jessica's music
Answer:
3 times louder than Jessica's music
Explanation:
You matter .
Until you Multiply yerself by the speed of Light Squared.
Then you Energy.
Answer:
Hellow ❤️
.
.
Gooood Morning
Answer:
?
Explanation:
I thought we were talking about a Flashpoint or something?
Fusion produces less radioactivity than fission.
True or false
Answer:
False
Explanation:
Fusion doesn't produce more.
Danielle took an iron nail and wrapped thin copper wire around it, then connected the ends of the copper wire to a battery. Which force or forces can Danielle's device produce?
Answer:
yes her device can produce
Explanation:
An electromagnetic force is produced by this setup.
The question suggests the construction of a solenoid with an iron core.I have attached an image. A solenoid has an iron core wrapped around by insulating wires. When the insulating wires are connected to a battery or a voltage source, current flows in the wire and travels through the wrapped region around the iron core. Now, this current produces a magnetic field inside the solenoid, directed along the axis of the solenoid. When the iron core comes under the influence of this magnetic field, it magnetizes and acts as a strong magnet and can produce magnetic force. The force generated through this process is called electromagnetic force.
When the battery is removed, the solenoid returns to its original state, which is it doesn't act as a magnet anymore. By the way, iron retains some magnetization.
Learn more about electromagnetic force:
https://brainly.com/question/13745767
The carbon cycle relies on producers and consumers to survive. What is the role of each in the carbon cycle?
Fast food meals are typically high in all except 1 fat 2 calories 3 sodium 4 fiber
Answer: they are high in all except fiber
Which is one use of lasers
A. reproducing images to make them clearer
B. Producing a magnified image of the moon
C. Cutting an iron bar into two pieces
D. Making a leaf appear larger so it’s veins are visible
Answer:
c
Explanation:
because what else can the laser be used for
A block of density 8.9g/cm³ measures 5cm by 2cm, Given that the force of gravity is 10N/kg. Determine the maximum pressure
Answer:
Maximum pressure = 4450 N/m²
Explanation:
We'll begin by calculating the volume of the block. This can be obtained as follow:
Volume (V) = 5 cm × 3 cm × 2 cm
V = 30 cm³
Next, we shall determine the mass of the block. This can be obtained as follow:
Density = 8.9 g/cm³
Volume = 30 cm³
Mass =?
Density = mass /volume
8.9 = mass / 30
Cross multiply
Mass = 8.9 × 30
Mass = 267 g
Next, we shall covert 267 g to Kg.
1000 g = 1 Kg
Therefore,
267 g = 267 g × 1 Kg / 1000
267 g = 0.267 Kg
Thus, the mass of the block is 0.267 Kg
Next, we shall determine the force.
Force of gravity (g) = 10 N/Kg
Mass (m) = 0.267 Kg
Force (F) =?
F = mg
F = 0.267 × 20
F = 2.67 N
Next, we shall determine the minimum area since we are trying to obtain the maximum pressure. This can be obtained as follow:
Minimum area = 3 cm × 2 cm
Covert each measurement to metre (m) by dividing each measurement by 100
Minimum area = 0.03 m × 0.02 m
Minimum area = 0.0006 m²
Finally, we shall determine the maximum pressure. This can be obtained as follow:
Force (F) = 2.67 N
Minimum area = 0.0006 m²
Maximum pressure =?
Maximum pressure = Force /minimum area
Maximum pressure = 2.67 / 0.0006
Maximum pressure = 4450 N/m²
6
Which of these statements is true?
А
Acceleration in the direction of motion slows you down
B.
Acceleration in the direction of motion speeds you up
C
Acceleration against the direction of motion has no effect
on your speed
D
Acceleration against the direction of motion speeds you up
Answer:
B. Acceleration in the direction of motion speeds you up
Explanation:
Acceleration is defined as when something gains speed. For example, when a car speeds up. Deceleration is when the car slows down, and looses speed. When defining these terms, think of a car going faster, then slowing down at a red light.
What is the frequency of a wave with a period of 8s?
1. Give 3 examples of waves that carry small amounts of energy?
ANSWER:
Radio wavesMicro wavesInfrared wavesAnswer those 2 questions.
What factors affect Kinetic Energy? a. Mass and Height b. Velocity and Time C. Mass and Velocity d. Mass and Time
What factors affect Potential Energy? a. Mass and Height b. Velocity and Time c. Mass and Velocity d. Mass and Time
Answer:
Q1: c
Q2: a
Explanation:
you can tell the factors by looking at the formulas for kinetic and potential energy
for question 1 look at the formula for kinetic energy
[tex]KE=\frac{1}{2} mv^{2}[/tex]
the variables needed in order to calculate an object's kinetic energy are mass and velocity.
hence, when mass and velocity changes, kinetic energy changes, showing that mass and velocity are the factors affecting kinetic energy
same thing for the second question
[tex]PE = mgh[/tex]
as g (acceleration due to gravity) is considered constant (10 [tex]m/s^{2}[/tex] ) it will not be considered as a factor
and thus, the factors affecting potential energy are mass and height
A pendulum has 12 cycles in 3 second. What is its frequency?
a.15Hz
b.4Hz
c.36Hz
d.9Hz
Which of the following explanations is correct about the wave that travels through the medium?
A. The vibration that produced the wave must have been perpendicular to the direction of motion of the resulting wave, because the figure shows that the resulting wave is a longitudinal wave.
B. The vibration that produced the wave must have been perpendicular to the direction of motion of the resulting wave, because the figure shows that the resulting wave is a transverse wave.
C. The vibration that produced the wave must have been parallel to the direction of motion of the resulting wave, because the figure shows that the resulting wave is a longitudinal wave.
D. The vibration that produced the wave must have been parallel to the direction of motion of the resulting wave, because the figure shows that the resulting wave is a transverse wave.
HELP ME PLEASEeeeeèeeeee
9514 1404 393
Answer:
5) 0.64Ω
6) 0.16 W
Explanation:
Put the given numbers into the given formula and do the arithmetic.
5)
[tex]\text{ohms}=\dfrac{\text{volts}}{\text{amps}}=\dfrac{0.32\text{ V}}{0.50\text{ A}}=\boxed{0.64\ \Omega}}[/tex]
__
6)
[tex]\text{watts}=\text{volts}\times\text{amps}=(0.32\text{ V})\times(0.50\text{ A})=\boxed{0.16\text{ W}}[/tex]
Answer:
just ok02
#CARRYONLEARNING
What are some ways I can have a good wardrobe without breaking the bank?
Function: y = x2 + 5x - 7
Vertex:(
Solutions:(
and
Answer:=7x−7
Explanation:
=2x+5x+−7
=(2x+5x)+(−7)
=7x+−7
what must happen in order for a metaphoric rock to be transformed into a igneous rock
Answer:
If the newly formed metamorphic rock continues to heat, it can eventually melt and become molten (magma). When the molten rock cools it forms an igneous rock.
Explanation:
Find the average acceleration of a northbound subway train that slows down from 12 m/s to 9.6 m/s in 0.8 seconds.
Answer:
[tex]a=-3\ m/s^2[/tex]
Explanation:
Given that,
Initial speed of a train, u = 12 m/s
Final speed of a train, v = 9.6 m/s
Time taken, t = 0.8 s
We need to find the average acceleration of the train. We know that the rate of change of velocity is equal to acceleration. So,
[tex]a=\dfrac{v-u}{t}\\\\a=\dfrac{9.6-12}{0.8}\\\\a=-3\ m/s^2[/tex]
So, the average acceleration of the train is equal to [tex]-3\ m/s^2[/tex].
Ingrid says that a red ball of clay appears red because the clay reflects red wavelengths. Simon says that the clay appears red because it allows red wavelengths to pass through it.
Which statement best explains who is correct?
Ingrid is correct. The clay appears red because it reflects red wavelengths.
Ingrid is correct. The clay appears red because it is a type of matter.
Simon is correct. The clay appears red because it allows red wavelengths to pass through it.
Simon is correct. The clay appears red because it is a solid.
Answer: (A) Ingrid is incorrect. The clay appears red because it reflects red wavelengths.
Explanation:
Edge 2021
Ingrid is correct. The clay appears red because it reflects red wavelengths.
Hence option A is correct.
What is wave ?Wave is is a disturbance in a medium that carries energy as well as momentum . wave is characterized by amplitude, wavelength and phase. Amplitude is the greatest distance that the particles are vibrating. especially a sound or radio wave, moves up and down. Amplitude is a measure of loudness of a sound wave. More amplitude means more loud is the sound wave.
Wavelength is the distance between two points on the wave which are in same phase. Phase is the position of a wave at a point at time t on a waveform.
There are two types of the wave longitudinal wave and transverse wave.
Longitudinal wave : in which, vibration of the medium (particle) is parallel to propagation of the wave. Sound wave is a longitudinal wave. Transverse wave : in which, vibration of the medium (particle) is perpendicular to propagation of the wave. Light wave is a Transverse wave.
Ingrid says that a red ball of clay appears red because the clay reflects red wavelengths. this statement is true.
Hence option A is correct.
To know more about absorption :
https://brainly.com/question/3080788
#SPJ7.
Find the acceleration of a body of mass 300g being acted upon by a force of 6N.
Please show the working
Answer:
20m/s^2
Explanation:
what is the name often given to the force exerted by the first object on a second object
The first published controlled experiment was designed to
A.
disprove bacteria appearing spontaneously from broth
B.
prove that bacteria arise spontaneously from broth
C.
disprove maggots spontaneously arising from rotting meat
D.
disprove cell theory
A student is blowing against the mouthpiece of a 668mm flute (open at both ends) causing it to resonate. (The air inside and outside the flute is 24.5°C)
1) what is the speed of the sound in the flute?
2) what is the fundamental frequency of the note produced?
3) what is the wavelength of the sound wave?
Answer:
a) v = 345.5 m / s, b) f = 183.8 Hz, c) λ = 1,336 m
Explanation:
a) the speed of sound depends on the density of the medium and this depends on the temperature, therefore
v = [tex]v_o \ \sqrt{1+ \frac{T}{273} }[/tex]
where v₀ is the speed of sound at 0ºC v₀ = 331 m / s
v = 331 [tex]\sqrt{1 + \frac{24.5}{273} }[/tex]
v = 345.5 m / s
c) In the exercise they indicate that the flute is a tube with the two ends open, so that at each end there is a belly, the resonance is
λ / 2 = L
λ = 2L
λ = 2 0.668
λ = 1,336 m
b) let's apply the relationship between speed, wavelength and frequency
v = λ f
f = v /λ
f = 345.5 / 1.336
f = 183.8 Hz
A student is observing prokaryotic and eukaryotic cells. How can the student determine the difference in the two cells?
Answer:
Prokaryotes are single-celled organisms that do not have a nucleus or any membrane-bound organelles. Eukaryotes are single-celled or multi-celled organisms that do contain a nucleus and membrane-bound organelles
During an experiment a student records the net horizontal force exerted on an object moving in a straight line along a horizontal frictionless track. The graph above shows the force as a function of time. Of the following, which is the best approximation of the magnitude of the change in momentum of the object between 0 s and 4 s? (A) 20 kg•m/s (B) 30 kg•m/s (C) 40 kg•m/s () The magnitude of the change in momentum
Answer:c 40kg
Explanation:
Answer:
B. 30 kg * m/s
Explanation:
college board answer