Answer:
A.) The particles that make up material A have more mass than the
particles that make up material B.
HOPE that helps!!! :)
You push a bike pedal 10cm and the bike moves 100cm. Calculate the Speed ratio ( show all work ) ( use the formula and divide the input distance by the output distance)
Answer:
when you are pushing the pedal you are causing the pedal to move done and then you will move 100cm
Explanation:
10 cm= 100 cm moved so when you move you will move because you are timeing the 10 by 100 to get the spped
if the distance between 2 troughs is 2.6 meters and a wave is traveling at a speed of 129 m/s, find the period of the wave
The period of the wave is the inverse of the frequency. The distance between the two successive crest or troughs is known as the wavelength. The period of the wave is 0.020 s.
What is period of a wave?The time taken by the particle of the medium to complete one vibration is defined as the period of the wave. The number of oscillations per second is known as the frequency. The equation used to calculate the period of a wave is:
T = 1 / f
The frequency of a wave is:
f = ν / λ
f = 129 m/s / 2.6 m
f = 49.6 Hz
Then the period of a wave is:
T = 1 / f
T = 1 / 49.6
T = 0.020 s
Thus the period of a wave is 0.020 s.
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help will mark and 5 stars
What is the average repetition or time for squats?
is the relationship between gravitational force and the distance between the planet centers an inverse or direct relationship?
The relationship between gravitational force and the distance between the centers of two planets is an inverse relationship.
According to Newton's law of universal gravitation, the force of attraction between two objects is directly proportional to their masses and inversely proportional to the square of the distance between their centers. In other words, as the distance between two planets increases, the force of gravity between them decreases.
This relationship can be explained by considering the way gravity works. Gravity is a force that results from the curvature of spacetime caused by massive objects. The more massive an object is, the more it curves the surrounding spacetime, and the stronger its gravitational pull. However, as the distance between two massive objects increases, the curvature of spacetime caused by one object becomes less and less significant on the other object. Therefore, the gravitational force between them decreases as the distance between them increases.
This inverse relationship between gravitational force and distance has important implications for our understanding of the universe. For example, it helps explain why planets in our solar system have stable orbits around the sun. As the planets move farther away from the sun, the gravitational force decreases, but their orbital speed decreases as well, keeping them in balance.
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a student placed 700g of water at 28C in a freezer. After 6 minutes and 15 seconds the water was transformed into ice. Calculate the latent heat of fusion given that 235200J of heat energy was transferred during the change of state
The latent heat of fusion is 335714.29 J/kg.
To calculate the latent heat of fusion, we can use the equation:
Q = m * L
Where:
Q = heat energy transferred
m = mass of the substance
L = latent heat of fusion
Given:
Mass of water (m) = 700 g = 0.7 kg
Heat energy transferred (Q) = 235200 J
To find the latent heat of fusion (L).
Since the water is being transformed into ice, we know that the heat energy transferred during this phase change is equal to the latent heat of fusion.
Rearrange the equation to solve for L:
L = Q / m
L = 235200 J / 0.7 kg
L ≈ 335714.29 J/kg
Therefore, the latent heat of fusion is approximately 335714.29 J/kg.
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Calculate the pressure on a man’s foot when a woman of mass 65 kg steps on his foot with her heel which has an area of 0.12m2 with all her weight.
Answer:
Pressure = force/area
= 650N/0.12m^2
= 5416.7 to 1 d.p
I got 650N by taking the gravitational field on earth to be 10N/kg.
Weight = mass x gravitational field
= 65 x 10N/kg
= 650
Answer is 5416.7 pascals (Pa)
Or
5308.3 Pa
if gravitational field was taken to be 9.8N/kg
Hope this helps!
Which of the following is a way that trees have been negatively impacted by human use? a. Deforestation b. Pollution c. Reduction d. All of the above Please select the best answer from the choices provided A B C D.
Answer:
D
Explanation:
Trees are obviously effected from deforestation.
Pollution effects the things trees need to grow (water, air).
Reduction removes parts of the tree, some parts being needed.
Answer: D
Explanation:Trees are obviously effected from deforestation.
Pollution effects the things trees need to grow (water, air).
Reduction removes parts of the tree, some parts being needed.
What rate do things fall to Earth?
Answer:
9.8 meters per square second
Explanation:
Free Falling Object. the value of g is 9.8 meters per square second on the surface of the earth. The gravitational acceleration g decreases with the square of the distance from the center of the earth. But for many practical problems, we can assume this factor to be a constant.
What is the fnet of the last fbd on the right
The net force which acts in the right direction of free body diagram is opposite of the frictional force acting on box. The force acting in the right direction is balanced by the frictional force. Therefore, the net force acting along the right direction is 20 N which means last option is correct.
4. A pipe enters a water tank at a point 6.50 m below
the surface of the contained water. What is the
water pressure in this pipe?
Answer:
165 kPa
Explanation:
Absolute pressure is:
P = Patm + ρgh
where Patm is the atmospheric pressure,
ρ is the density,
g is acceleration due to gravity,
and h is the depth.
P = 101,300 Pa + (1000 kg/m³) (9.8 m/s²) (6.50 m)
P = 165,000 Pa
P = 165 kPa
To make a perfect pie dough, you must mix the ingredients until they are
O
O
assiduous
cohesive
coalition
abstract
The best pie crust is a perfect balance between fat, flour, and liquid. is
To make a perfect pie dough .
Why is it called pie?"Pie" was the word for a magpie before it was a word for a pastry, from the Latin word for the bird, Pica (whence the name of the disorder that makes you eat weird things). Pica morphed into "pie" in Old French, following the proud French tradition of actually pronouncing as few consonants as possible.
What is in pie?pie, dish made by lining a shallow container with pastry and filling the container with a sweet or savoury mixture. A top crust may be added; the pie is baked until the crust is crisp and the filling is cooked through.
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The ideal proportion of oil, flour, and liquid goes into making the greatest pie crust. is to create the ideal pie dough.
How come it's called pie?Before it became a term for a baked food, "pie" was the Slang phrase for bird, Pix (whence the name of the disorder that makes you eat weird things). Following their noble French custom of genuinely speaking as few letters as possible, pica evolved into "pie" during Old French.
How is pie made?Pie is a dish that is created by lining the shallow dish with dough and filling it with either a sweet or spicy combination. Its pie is heated until the filling is heated all the way through and the top crust is crunchy.
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relief supplies are being dropped to flood victims from an airplane flying horizontally at a speed v. if the airplane is at an altitude of h above the ground, what distance d in front of the landing site should the supplies be dropped?
The distance d in front of the landing site should the supplies be dropped is v√(2h/g) meter. If the horizontal velocity of the airplane is v m/s and height of the plane from the ground is h.
Horizontal velocity of the airplane = v
height of the airplane = h
Initial velocity of the food, u = 0 m/s
From the second equation of motion,
S = ut +0.5gt²
h = 0.5gt²
t = √(2h/g)
It is time taken by the food to reach the ground. in this time the horizontal distance travelled by the food is, d = v × t
d = v × √(2h/g)
d = v√(2h/g)
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an object is moving with a velocity in the positive direction. if the object experiences an acceleration opposite the direction of its motion what would it be
Answer:
A negative acceleration
Explanation:
It moves opposite of poistive so it then becomes negative.
When an object is moving with a velocity in the positive direction. if the object experiences an acceleration opposite the direction of its motion, then the object would deaccelerate due to the effect of the negative acceleration which is also known as deacceleration.
What is acceleration?The rate of change of the velocity with respect to time is known as the acceleration of the object.
When an item is traveling with a positive direction velocity. The term "deacceleration" refers to the phenomenon when an item experiences a negative acceleration, which is the opposite of the direction in which it is moving.
Thus, the moving object would deaccelerate because of the acceleration in the negative direction.
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Burning fossil fuels does not substantially impact the amount of carbon in
the atmosphere over time.
O True
O False
Answer: False.
Explanation:
Over the last century, burning of fossil fuels like coal and oil has increased the concentration of atmospheric carbon dioxide (CO2). This increase happens because the coal or oil burning process combines carbon with oxygen in the air to make CO2.
Hope this helps :)
Question 2 options:
A ________ is an ability that allows you to perform a specific task effectively.
Answer: The answer is Skill
Explanation:
HELP ASAP ILL DO ANYTHING.!!!!!!
Why does ice cream melt when you are holding it in a cone but not when it is sitting
in the freezer? Answer in terms of particles.
Answer: the heat from the environment melts the ice cream. When it’s in the freezer it doesn’t melt because both the freezer and ice cream are the same temperature
Explanation:
Answer:
the freezer and the ice cream is at the same temp while your hand and the cone is warmer so he heat from the cone transfers to the ice cream and heat it up and its particles move faster as it changes from a solid to a liquid.
You can add an easy question and give me some points if you would like!
state and explain the joules law
Answer:
Joule’s law of heating states that when a current ‘i ' passes through a conductor of resistance ‘r’ for time ‘t’ then the heat developed in the conductor is equal to the product of the square of the current, the resistance and time.
H = i 2 rt
The reason behind the heat produced is the collision of the free electrons with the lattice ions or atoms while accelerating in presence of the external electric field.
we know that
volt= work done/ total charge or v = w/q
from this we get w= vq
we know that current i = q / t
so q = it
putting this in prev equation
we get w = vit
from ohms law v = ir
putting it in prev eq we get
w = irit = i2rt joule as work is stored as heat soH = I2RT Joules
if a current carrying conductor having resistance (r) gets heated by to passing of current (i) for time (t) and the heat thereby produced be H
joules law states that
H propotional to i^ 2 when r and t are constant
H propotional to r when I and t are constant
H propotional to t when r and I constant
What should be done in order to decrease the gravitational force between two objects?
Increase the distance between the two objects.
Increase the mass of both of the objects.
Increase the mass of one of the objects.
Decrease the distance between the two objects.
Answer:
Actually for people in K12 (me) the answer is, "Increase the distance between the two objects"
Explanation:
I used the answer above me and got it wrong
:))
Answer: increase the distance between the two objects
Explanation: its the correct one trust me
A coin falls off a table and is traveling to the ground. Which claim about the forces acting on the coin must be true?
(Choice A)
There is a net force on the coin.
(Choice B)
There are no forces on the coin.
(Choice C)
There is no net force on the coin.
(Choice D)
There is not enough information.
A coin falls off a table and is traveling to the ground. There is a net force on the coin which is responsible for the motion of the coin. Thus, the correct option is A.
What is Net force?The net force can be defined as is the sum of all the forces which are acting on an object. Net force acting upon an object can accelerate its mass. Some other forces also acts on a body either at rest or motion. The net force is used in a system when there is a significant number of forces acting on the object.
A coin which falls off a table and is still traveling to the ground. Then, it can be concluded that there is a net force which is acting on that coin which is responsible for the motion of the coin.
Therefore, the correct option is A.
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what is the charge of an ion that has 15 protons 16 neutrons
Answer:carbon
Explanation:
An airplane travels down a
runway for 4.0 seconds with an
acceleration of 9.0 m/s2. What
its change in velocity during
this
time?
Someone helpppp!!
Answer:
We can use the equation of motion of an object under constant acceleration to calculate the change in velocity during this time. The equation is:
Δv = at
Where:
Δv = change in velocity (m/s)
a = acceleration (m/s^2)
t = time (s)
Given that the acceleration of the airplane is 9.0 m/s^2 and the time it travels down the runway is 4.0 seconds we can substitute these values into the equation:
Δv = 9.0 m/s^2 * 4.0 s = 36 m/s
Therefore, the change in velocity of the airplane during this time is 36 m/s.
A mass of 1 slug is suspended from a spring whose spring constant is 9 lb/ft. The mass is initially released from a point 1 foot above the equilibrium position with an upward velocity of Ï3 ft/s. Find the times at which the mass is heading downward at a velocity of 3 ft/s.
Answer:
t = 5π/18 + 2nπ/3 or π/6 + 2nπ/3 where n is a natural number
Explanation:
To solve the problem/ we first write the differential equation governing the motion. So,
\(m\frac{d^{2} x}{dt^{2} } = -kx \\ m\frac{d^{2} x}{dt^{2} } + kx = 0\\\frac{d^{2} x}{dt^{2} } + \frac{k}{m} x = 0\)
with m = 1 slug and k = 9 lb/ft, the equation becomes
\(\frac{d^{2} x}{dt^{2} } + \frac{9}{1} x = 0\\\frac{d^{2} x}{dt^{2} } + 9 x = 0\)
The characteristic equation is
D² + 9 = 0
D = ±√-9 = ±3i
The general solution of the above equation is thus
x(t) = c₁cos3t + c₂sin3t
Now, our initial conditions are
x(0) = -1 ft and x'(0) = -√3 ft/s
differentiating x(t), we have
x'(t) = -3c₁sin3t + 3c₂cos3t
So,
x(0) = c₁cos(3 × 0) + c₂sin(3 × 0)
x(0) = c₁cos(0) + c₂sin(0)
x(0) = c₁ × (1) + c₂ × 0
x(0) = c₁ + 0
x(0) = c₁ = -1
Also,
x'(0) = -3c₁sin(3 × 0) + 3c₂cos(3 × 0)
x'(0) = -3c₁sin(0) + 3c₂cos(0)
x'(0) = -3c₁ × 0 + 3c₂ × 1
x'(0) = 0 + 3c₂
x'(0) = 3c₂ = -√3
c₂ = -√3/3
So,
x(t) = -cos3t - (√3/3)sin3t
Now, we convert x(t) into the form x(t) = Asin(ωt + Φ)
where A = √c₁² + c₂² = √[(-1)² + (-√3/3)²] = √(1 + 1/3) = √4/3 = 2/√3 = 2√3/3 and Ф = tan⁻¹(c₁/c₂) = tan⁻¹(-1/-√3/3) = tan⁻¹(3/√3) = tan⁻¹(√3) = π/3.
Since tanФ > 0, Ф is in the third quadrant. So, Ф = π/3 + π = 4π/3
x(t) = (2√3/3)sin(3t + 4π/3)
So, the velocity v(t) = x'(t) = (2√3)cos(3t + 4π/3)
We now find the times when v(t) = 3 ft/s
So (2√3)cos(3t + 4π/3) = 3
cos(3t + 4π/3) = 3/2√3
cos(3t + 4π/3) = √3/2
(3t + 4π/3) = cos⁻¹(√3/2)
3t + 4π/3 = ±π/6 + 2kπ where k is an integer
3t = ±π/6 + 2kπ - 4π/3
t = ±π/18 + 2kπ/3 - 4π/9
t = π/18 + 2kπ/3 - 4π/9 or -π/18 + 2kπ/3 - 4π/9
t = π/18 - 4π/9 + 2kπ/3 or -π/18 - 4π/9 + 2kπ/3
t = -7π/18 + 2kπ/3 or -π/2 + 2kπ/3
Since t is not less than 0, the values of k ≤ 0 are not included
So when k = 1,
t = 5π/18 and π/6. So,
t = 5π/18 + 2nπ/3 or π/6 + 2nπ/3 where n is a natural number
The time interval at which the mass will head downward at the velocity of 3 ft/s is t = 5π/18 + 2nπ/3.
Given data:
The mass suspended from spring is, m = 1 slug.
The spring constant is, k = 9 lb/ft.
The magnitude of upward velocity is, v = 3 ft/s.
The magnitude of downward velocity is, v' = 3 ft/s.
The given problem can be resolved by framing a differential equation that governs the motion of spring. The differential equation governing the motion of spring is,
\(m \dfrac{d^{2}x}{dt^{2}}=-kx\\\\\\\dfrac{d^{2}x}{dt^{2}}+\dfrac{k}{m}x=0\)
With m = 1 slug and k = 9 lb/ft, the equation becomes
\(\dfrac{d^{2}x}{dt^{2}}+\dfrac{9}{1}x=0\\\\\\\dfrac{d^{2}x}{dt^{2}}+9x=0\)
Now, the characteristic equation is,
D² + 9 = 0
D = ±√-9 = ±3i
And the general solution of the above equation is,
x(t) = c₁cos3t + c₂sin3t
Now, our initial conditions are
x(0) = -1 ft and x'(0) = -√3 ft/s
differentiating x(t), we have
x'(t) = -3c₁sin3t + 3c₂cos3t
So,
x(0) = c₁cos(3 × 0) + c₂sin(3 × 0)
x(0) = c₁cos(0) + c₂sin(0)
x(0) = c₁ × (1) + c₂ × 0
x(0) = c₁ + 0
x(0) = c₁ = -1
Also,
x'(0) = -3c₁sin(3 × 0) + 3c₂cos(3 × 0)
x'(0) = -3c₁sin(0) + 3c₂cos(0)
x'(0) = -3c₁ × 0 + 3c₂ × 1
x'(0) = 0 + 3c₂
x'(0) = 3c₂ = -√3
c₂ = -√3/3
So,
x(t) = -cos3t - (√3/3)sin3t
Now, we convert x(t) into the form x(t) = Asin(ωt + Φ)
where A = √c₁² + c₂²
= √[(-1)² + (-√3/3)²]
= √(1 + 1/3) = √4/3 = 2/√3 = 2√3/3
and Ф = tan⁻¹(c₁/c₂) = tan⁻¹(-1/-√3/3) = tan⁻¹(3/√3) = tan⁻¹(√3) = π/3.
Since tanФ > 0, Ф is in the third quadrant. So, Ф = π/3 + π = 4π/3
x(t) = (2√3/3)sin(3t + 4π/3)
So, the velocity v(t) = x'(t) = (2√3)cos(3t + 4π/3)
We now find the times when v(t) = 3 ft/s
So (2√3)cos(3t + 4π/3) = 3
cos(3t + 4π/3) = 3/2√3
cos(3t + 4π/3) = √3/2
(3t + 4π/3) = cos⁻¹(√3/2)
3t + 4π/3 = ±π/6 + 2kπ
where k is an integer
3t = ±π/6 + 2kπ - 4π/3
t = ±π/18 + 2kπ/3 - 4π/9
t = π/18 + 2kπ/3 - 4π/9 or -π/18 + 2kπ/3 - 4π/9
t = π/18 - 4π/9 + 2kπ/3 or -π/18 - 4π/9 + 2kπ/3
t = -7π/18 + 2kπ/3 or -π/2 + 2kπ/3
Since t is not less than 0, the values of k ≤ 0 are not included
So when k = 1,
t = 5π/18 and π/6.
t = 5π/18 + 2nπ/3
here, n is a natural number.
Thus, we can conclude that the time interval at which the mass will head downward at the velocity of 3 ft/s is t = 5π/18 + 2nπ/3.
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A toy train with a mass of 2 kg moving at 10 m/s collides with a 2-kg toy train that is
stationary. If the two trains move together after the collision, what will be their speed after impact
Because momentum will be conserved, their common speed after impact will be 5 m/s
Third Newton's Law of MotionThe third Newton's law of motion states that in any action, there will be equal and opposite reaction.
Given that a toy train with a mass of 2 kg moving at 10 m/s collides with a 2-kg toy train that is stationary. If the two trains move together after the collision, their speed V after impact can be calculated through the formula
M1U1 + M2U2 = (M1 + M2)V
The given parameters are
M1 = 2 kgU1 = 10 m/sM2 = 2kgU2 = 0V = ?Substitute all the parameters into the formula
2 × 10 + 2 × 0 = (2 + 2)V
20 = 4V
V = 20/4
V = 5 m/s
Therefore, their speed after impact is 5 m/s
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Two large parallel conducting plates carry charges of equal magnitude and opposite charge. When you place a point charge q = +3.60 nC between the plates, the force on the point charge is 22.0 μN. What is the magnitude of the surface charge density on either plate? Express your answer with the appropriate units.
Answer:
The magnitude of the surface charge density on either plate is approximately 5.41 × 10⁻⁸ C/(m²)
Explanation:
The magnitude of the charge on each of the conducting plates = Equal
The orientation of the charges on each plate = Opposite charges
The magnitude of the point charge placed between the plates = +3.60 nC
The force acting on the point charge, q = 22.0 μN
Therefore, we have;
F = E × q
E = F/q = 22.0 μN/+3.60nC = 6,111.1111 V/m
We have;
\(E = \dfrac{\rho }{\epsilon_0}\)
Where;
ρ = The surface charge density
ε₀ = Absolute permittivity ≈ 8.85 × 10⁻¹² C²/(N·m²)
Therefore, we have;
ρ = E × ε₀ = 6,111.1111 V/m × 8.85 × 10⁻¹² C²/(N·m²) = 5.40833332 × 10⁻⁸ C/(m²)
∴ The magnitude of the surface charge density on either plate, ρ ≈ 5.41 × 10⁻⁸ C/(m²).
What is the minimum length of time water must remain motionless in service lines prior to first-draw residential lead sampling?
a) 2 hours
b) 4 hours
c) 6 hours
d) 8 hours
The recommended minimum length of time that water should remain motionless in service lines prior to first-draw residential lead sampling is 6 hours.
Lead can leach into drinking water from the service lines and plumbing fixtures, particularly in older homes that may have lead pipes or lead-based solder. When water sits stagnant in these pipes for a period of time, such as overnight or during the day when no one is home, the lead particles that have accumulated in the plumbing system can dissolve into the water. This is why it's important to collect first-draw samples after a period of stagnation.
The EPA recommends a 6-hour stagnation period for collecting first-draw samples from residential plumbing systems because this is typically the longest period of time that water remains stagnant in home plumbing systems. This means that the water has been sitting in the pipes long enough to allow any lead particles to leach into the water, but not so long that the water quality may be affected by other factors, such as microbial growth or chemical reactions.
It's important to note that first-draw samples are used to identify the presence of lead in the plumbing system, but they may not be representative of the actual exposure to lead that a person may experience. This is because the lead concentration in the water can vary depending on factors such as the age and condition of the plumbing system, the water chemistry, and the length of time that water has been sitting in the pipes.
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select three parts of a circular saw
spindle
trigger
base
handle
key
chuck
Answer:
handle, trigger, spindle
A sound wave is observed to travel through a liquid with a speed of 1500 m/s. The specific gravity of the liquid is 1.5. Determine the bulk modulus for this fluid.
The bulk modulus for the fluid is approximately 3.375 × 10^9 Pa (Pascals).
What is the bulk modulus of a fluid with a specific gravity of 1.5, if the speed of sound through the fluid is 1500 m/s?To determine the bulk modulus (K) for the fluid, we can use the formula:
K = ρ * v^2
where ρ is the density of the fluid and v is the speed of sound in the fluid.
- Speed of sound in the fluid (v) = 1500 m/s
- Specific gravity of the fluid = 1.5
The specific gravity is the ratio of the density of the fluid to the density of water. Since water has a density of 1000 kg/m^3, we can find the density of the fluid (ρ) as:
ρ = Specific gravity * Density of water
= 1.5 * 1000 kg/m^3
= 1500 kg/m^3
Substituting the values into the bulk modulus formula:
K = (1500 kg/m^3) * (1500 m/s)^2
Calculating this expression will give us the value of the bulk modulus for the fluid.
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A 10- kilogram box is at static equilibrium and the downward pull of gravity acting on the box is 98 Newton's what is the minimum force that would be required to just pick up the box ?
Answer:
Explanation:
Now
Look at it this way. This box is in equilibrium... Meaning forces around balanced out.
Now...
The Earth's pull on it is 98N
What Minimum external forces is needed to pick this up....
Now... The Minimum Force is 98N
Why?
Since This Box is under the influence of gravity...
Gravity is acting as a resistance
If you apply a force less than 98N... Let's say 50N on this box... It won't budge because your applied force is less than the resisting force on it(98N).
So We need a force ≥98. So the least force is 98N. Nothing below this will move the Box
Answer 98N.
Answer:
See image
Explanation:
Plato
7. Which best describes the energy change th pushes a large rock down a hill?
A: sound energy kinetic energy
B:, potential energy kinetic energy
C: kinetic energy mechanical energy
D: mechanical energy sound energy
Answer:
B
Explanation:
Gravitational Energy is the energy of position or place. A rock resting at the top of a hill contains gravitational Potential energy. Hydropower, such as water in a reservoir behind a dam, is an example of gravitational potential energy.
Hanging from a tree branch is doing work?
Explanation:
The branch is possessing gravitational potential energy.