Answer: 121.2 m/s
Explanation:
Here we will use the conservation of energy.
We can write the total energy of an object as:
E = K + U
For this particular case we have:
K = kinetic energy = (m/2)*v^2
U = potential energy = m*g*h
where:
m = mass of the object.
g = gravitational acceleration = 9.8m/s^2
h = height at which the object is dropped, in this case 750m
v = velocity of the object.
Right when the packet is dropped, it's velocity is equal to zero, this means that there is no kinetic energy and only potential energy, then we have:
Ei = Ui = m*9.8m/s^2*750m = m*(7350m^2/s^2)
And when the object is about to hit the ground, h will be almost equal to zero, this will mean that we will have only kinetic energy, and because of the conservation of energy, this final energy must be the same as the initial energy, then we will have
Ei = Ef
m*(7350m^2/s^2) = Ef = Kf
m*(7350m^2/s^2) = (m/2)*v^2
We can divide by m in both sides to get:
(7350m^2/s^2) = (1/2)*v^2
√( 2*(7350m^2/s^2)) = v = 121.2 m/s
Then the velocity of the packet when it reaches the ground is 121.2 m/s
Which of these games was a racing game?
A.
Centipede
B.
Pole Position
C.
Xevious
D.
Galaxian
E.
Space Invaders
Answer:
B.
pole position
Which of these is an example of electrical energy being converted to mechanical energy?
Group of answer choices
Sunlight used by plants in photosynthesis
Ceiling fan
Lightning striking the ground
Answer:
Ceiling fan
Explanation:
A ceiling fan is an example of electrical energy being converted to mechanical energy.
The blades of the fan are driven by motor within the system.
Energy in a system is converted from one form to the other. Energy is neither created nor destroyed as we know from the law of conservation of energy. In this regard, the electrical energy from the outlet powers the motor. As the motor inside the fan spins, the blade in turn begins to rotate. The motion of the blade is the expression of mechanical energy.A baseball on the Moon and an identical baseball on the Earth are thrown vertically upward with the same initial velocity of 12 m/s. The acceleration due to gravity on the Moon is 1/6 that of Earth. What is the maximum height the ball reaches on the moon? What is the maximum height the ball reaches on the earth? What is the difference in the maximum height the ball reaches on the Moon compared to on Earth?
Answer:
a. 3.68 m b. 0.61 m c. 3.07 m
Explanation:
a. What is the maximum height the ball reaches on the moon?
Using v² = u² - 2g'h where u = initial velocity of baseball = 12 m/s, v = final velocity of baseball = 0 m/s (since it stops at maximum height), g' = acceleration due to gravity on moon = g/6 where g = acceleration due to gravity on earth = 9.8 m/s², so g' = 9.8 m/s²/6 = 1.63 m/s² and h = maximum height of ball on moon.
So, making h subject of the formula, we have
h = -(v² - u²)/2g'
substituting the values of the variables, we have
h = -((0 m/s)² - (12 m/s)²)/2(1.63 m/s²)
= -(- 12 m²/s²)/2(1.63 m/s²)
= 6 m²/s²)/(1.63 m/s²)
= 3.68 m
b. What is the maximum height the ball reaches on the earth?
Using the same equation for the maximum height the baseball travels on the moon for that on the earth, the maximum height h' the baseball travels on the earth is given by
h' = -(v² - u²)/2g where u = initial velocity of baseball = 12 m/s, v = final velocity of baseball = 0 m/s (since it stops at maximum height), g = acceleration due to gravity on earth = 9.8 m/s²and h' = maximum height of ball on moon.
substituting the values of the variables, we have
h = -((0 m/s)² - (12 m/s)²)/2(9.8 m/s²)
= -(- 12 m²/s²)/2(9.8 m/s²)
= 6 m²/s²)/(9.8 m/s²)
= 0.61 m
c. What is the difference in the maximum height the ball reaches on the Moon compared to on Earth?
The difference in the maximum height the ball reaches on the Moon compared to on Earth is d = h - h' = 3.68 m - 0.61 m = 3.07 m
a man walks 30 meters north,then 90 meters east, and then 30 meters south
Explanation:
D = 30+90+30
= 150m
.............
what's the question
Help me please :))))))
Answer:
first one is d second is a
Explanation:
hope this helps luv
All power plants use fuel to supply energy that turns into:
Answer: Electrical energy
Explanation:
A power plant is considering an industrial facility that has the ability to generate electricity from its primary energy.
There could be used one or more generator when it comes to power plants and their function is to convert mechanical energy into electrical energy in order to supply power to the electrical grid for other people that are needing electricity and more.
the weight of a person is 400N. he exerts 400N/m² pressure if he stands with both feet. Find the area of the floor covered by his both feet.
Answer:
1 m²Explanation:
The area of the floor covered by his both feet can be found by using the formula
[tex]a = \frac{f}{p} \\ [/tex]
f is the force
p is the pressure
From the question we have
[tex]a = \frac{400}{400} = 1 \\ [/tex]
We have the final answer as
1 m²Hope this helps you
Hardin electronic corporation is designing a new cell phone, they need a solid material that will insulate the phone and product their users from electric shock. Which material would best fit the needs of Hardin engineers A. A non-metal B. A metalloid C. A metal D. A semiconductor
Answer:
A
Explanation:
The material that would best suit Hardin electronic corporation's need would be a non-metal.
Non-metals are naturally occurring substances or materials that lack the properties of metals. In other words, non-metals are poor conductors of heat and electricity, unlike metals.
Solid non-metals are, therefore, used as insulators in the design of materials. Hence, the best material for Hardin electronic corporation to use that will insulate the phone and protect their users from electric shock would be a non-metal.
The correct option is A.
A 10 N force and an 18 N force act in the same direction on an object. What is the net force on the object?
Answer:
28 N
Explanation:
From the question given above, we were told that 10 N force and 18 N force act in the same direction on the object.
The net force acting on the object can be obtained by simply adding both forces together since they both act on the object in the same direction. This is illustrated below:
Force 1 (F₁) = 10 N
Force 2 (F₂) = 18 N
Net force (Fₙ) =?
Fₙ = F₁ + F₂ (since they both act in the same direction)
Fₙ = 10 + 18
Fₙ = 28 N
Therefore, the net force acting on the object is 28 N.
Form hypothesis: How do you think increasing the resistance in a circuit will affect the current in the wire? (format: if, then, because)
Answer:it would make it thicker
Explanation:
Answer:
"The equation shows that the current in a circuit is inversely proportional to the resistance of the circuit. An increase in resistance would result in a decrease in current. And the factor by which the resistance increases is the same factor by which the current decreases."
Explanation:
Because it's just like wearing a glove/mitten when getting something out of the oven, because of the insulation from the glove/mitten, it reduces the heat that gets through into your hand, and it protects it. Just like what the "answer" says, it said that the resistance would decrease current.
If the person's velocity is changing is the person
accelerating
Answer:
a change in velocity can be a change in magnitude (or speed), but it can also be a change in direction.
1) A rock was thrown horizontally from a 500.0 m high cliff. It
strikes the ground 100.0 m from the base of the cliff. At
what speed was it thrown?
Answer:
twenty two miles per hour
Which of these is not a method of preventing the corrosion of metals?
A) galvanising
B) painting
C) plating
D) rusting
Answer:
D
Explanation:
rusting is actually the corrosion of metals so it can't be a way to prevent itself.
HELP ASAP
The Target employees are working hard to get the orders out to everyone. The employees need to move packages from the ground level to the top of the loading dock platform. As shown in Figure 1, the employee pushes the package up a ramp (you may assume friction is negligible). In figure 2, the employee lifts the package straight up from ground to the loading dock platform. In which case does the employee do more work on the box and why?
a
Lifting the box straight up, because the incline acts as a simple machine and reduces the force required
b
Lifting the box straight up, because it requires a larger applied force to lift it straight up
c
Pushing the box up the incline, because the force is applied for a longer distance
d
Neither method, because the work is the same in both cases, since using the ramp decreases the force by the same factor that it increases the distance
Answer:
I believe the answer is B
Jessica did an investigation about the states of matter. As part of the investigation, Jessica wanted to change a liquid into a solid. What must she do to bring about this change in state?
place the liquid in a different container
A
B
stir the liquid as quickly and thoroughly as possible
C
remove energy from the liquid so that its particles slow down
D
increase the energy of the liquid so that its particles move faster
Answer:
D : Increase the energy of the liquid so that its particles move faster
Explanation:
Sorry the other guy was wrong can i have brailiest please.
how many cups are in 4 gallons
Answer:
there are 64 cups
Explanation:
remember this: two cups in a pint, two pints in a quart, two pints in a quart, four quarts in a gallonl2
how longitudinal waves are formed
Answer:
forever
Explanation:
A car travels 300km in six hour. What is the average speed
Answer:
50 km/hrExplanation:
The average speed of the car can be found by using the formula
[tex]s = \frac{d}{t} \\ [/tex]
d is the distance
t is the time taken
From the question we have
[tex]s = \frac{300}{6} = 50 \\ [/tex]
We have the final answer as
50 km/hrHope this helps you
Answer:
50mph
Explanation:
Just do[tex]\frac{300}{6}[/tex] (aka 300 divided by 6)
And you'll get 50 as your answer!
Hope this helps! Ty!
An object is thrown straight up into the air with an initial speed of 8 m/s, and reaches a greatest height of 15 m before it falls back to the ground. a. What height is the object thrown from? b. How long does it take for the object to hit the ground?
Answer:
The value is [tex]T_t = 2.5659 \ s[/tex]
Explanation:
From the we are told that
The initial speed of the object is [tex]u = 8 \ m/s[/tex]
The greatest height it reached is [tex]h = 15 \ m[/tex]
Generally from kinematic equation we have that
[tex]v^2 = u^2 + 2gH[/tex]
At maximum height v = 0 m/s
So
[tex]0^2 = 8^2 + 2 * - 9.8 * H[/tex]
=> [tex]H = 3.27 \ m[/tex]
Here H is the height from the initial height to the maximum height
So the initial height is mathematically represented as
[tex]s = h - H[/tex]
=> [tex]s = 15 - 3.27[/tex]
=> [tex]s = 11.73 \ m[/tex]
Generally the time taken for the object to reach maximum height is mathematically evaluated using kinematic equation as follows
[tex]v = u + (-g) t[/tex]
At maximum height v = 0 m/s
[tex]0 = 8 - 9.8t[/tex]
=> [tex]t = 0.8163 \ s[/tex]
Generally the time taken for the object to move from the maximum height to the ground is mathematically using kinematic equation as follows
[tex]h = ut_1 + \frac{1}{2} gt_1^2[/tex]
Here the initial velocity is 0 m/s given that its the velocity at maximum height
Also g is positive because we are moving in the direction of gravity
So
[tex]15 = 0* t + 4.9 t^2[/tex]
=> [tex]t_1 = 1.7496[/tex]
Generally the total time taken is mathematically represented as
[tex]T_t = t + t_1[/tex]
=> [tex]T_t = 0.8163 + 1.7496[/tex]
=> [tex]T_t = 2.5659 \ s[/tex]
water starts to freeze from top whereas wax starts to freeze from bottom?why?
Answer:
im pretty sure its because wax has i higher melting point therefore it would cool quicker if the temperature dropped more. water has a lower melting point so it takes longer to freeze i think. i hope this helps
Water and wax freeze from different directions due to the unique properties and behaviors of these substances.
Water:
When water freezes, it undergoes a phase transition from a liquid to a solid state.
Unlike most substances, water exhibits an unusual property known as the "anomalous expansion of water" or "density anomaly." This anomaly is caused by the hydrogen bonding between water molecules.
As the water cools down, its molecules begin to slow down and move closer together. This causes the density of the water to increase. However, as the water reaches around 4 degrees Celsius (39 degrees Fahrenheit), it starts to behave differently.
The hydrogen bonds between water molecules become more organized and stable, causing the water to expand and become less dense.
Wax:
Wax, on the other hand, does not exhibit the same density anomaly as water. When wax undergoes solidification, it follows a different pattern due to its molecular structure and the way its particles arrange themselves.
Wax typically consists of long, nonpolar hydrocarbon chains. As it cools, the wax molecules start to lose kinetic energy, slowing down their movement.
The intermolecular forces between the wax molecules become stronger, causing them to come closer together.
In summary, water freezes from the top due to its density anomaly, with the less dense, expanded water rising and forming a layer of ice on the surface.
Wax, however, freezes from the bottom as its molecules arrange and bond together, gradually solidifying upwards. These differences in freezing behavior are influenced by the distinct properties and molecular structures of water and wax.
Know more about hydrogen bonds:
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pins accompained by a ball bowling dates back to what era
Which element accumulates in the environment due to the use of
fertilizers?
A. oxygen
B. hydrogen
C. nitrogen
D. carbon
To Find :
Which element accumulates in the environment due to the use of fertilizers.
Solution :
Most of the fertilizers used in daily practice are nitrogen fertilizers .
When soil became waterlogged, soil organisms take the oxygen they need from nitrates, leaving the nitrogen in a gaseous form which escapes into the air.
Also, nitrogen is very stable and did not participate in most of the reactions.
So, nitrogen is accumulates in the environment .
Therefore, option C. is correct.
Identify the type of motion that occurs when a body moves around its own center of mass.
circular
revolution
rotation
resolution
Answer:
circular
Explanation:
A person pours some chlorine bleach into a clothes washer to remove stains from the clothing. What is one chemical property or the bleach?
A. It’s density
B. It’s mass
C. It’s color
D. It’s pH
One chemical property of the bleach is its pH.
What is pH?This is referred to as the power of hydrogen and is a measure of how acidic/basic a substance is.
pH is an example of chemical property because it's associated with a change in its chemical composition. This thereby makes option D the most appropriate choice.
Read more about pH here https://brainly.com/question/4137247
Answer: It's pH
Explanation: I took the test
If you have 100 kg of each of these substances, which would require the most energy to increase its temperature by 25 Kelvin?
A. iron
B. carbon
C. rubber
D. air
Answer:
a
Explanation:
Answer:
A Iron
Explanation:
Hope this helps :D
where does reduction occur in an electrolytic cell
a. cathode
b. salt bridge
c. anode
d. wire
Answer:
The answer is actually a. Cathode
Explanation:
Just took the quiz
In an electrolytic cell, the reduction occurs at the cathode. So, the correct option is a.
What is meant by reduction ?Reduction is defined as the process through which a reactant gain electrons during a chemical reaction.
Here,
An electrolytic cell is an equipment that uses electric current to drive a redox reaction.
Redox reactions are the type of reaction that involves the transfer of electrons between the reactants. That means, in redox reactions, both oxidation and reduction occurs. The reactant that gains the electrons is said to be reduced and the one that losses the electrons is said to be oxidized.
In an electrolytic cell, cathode is the positively charged electrode. So, electrons are attracted towards it, and as a result, the cathode gets reduced.
Hence,
In an electrolytic cell, the reduction occurs at the cathode.
To learn more about reduction, click:
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21. A teacher does the following:
i. walks 4 m, south
ii. walks 8 m, east
iii. walks 4 m, north
iv. walks 8 m, west.
The overall displacement of the teacher is
a. Om
b. 6 m
c. 12 m
d. ... Nonsense! It cannot be calculated without knowing time information.
Answer:
displacement is the change from a starting point. she ends up back where she started so her displacement is zero meters although she traveled 24m in all.
Ronald observes a large island off the coast of Indonesia on a map. A few months later, he observes that there are many smaller islands in place of the large one he had seen earlier. Which of these could have caused this change?
Answer:
idgaf
Explanation:
lol
A pendulum swings back and forth. Is there energy in the system?
Answer:
yes
Explanation:
A pendulum should be able to contain enough energy to constantly be moving
A student wearing a frictionless roller skates on a horizontal is pushed by a friend with a constant force of 55N. How far must the student be pushed, starting from rest, so that her final kinetic energy is 362 J
Answer:
6.58m
Explanation:
The kinetic energy = Workdone on the roller
Workdone = Force * distance
Given
KE = Workdone = 362J
Force = 55N
Required
Distance
Substitute into the formula;
Workdone = Force * distance
362 = 55d
d = 362/55
d = 6.58m
Hence the student must push at a distance of 6.58m