Answer:
y = 20 [m]
Explanation:
To solve this type of problem we must use the following equation of kinematics.
[tex]v_{f}^{2} =v_{o}^{2}-2*g*y[/tex]
where:
Vf = final velocity = 0
Vo = initial velocity = 20 [m/s]
g = gravity acceleration = 10 [m/s²]
y = elevation [m]
Now the key to solving this problem is to know that when the stone reaches the maximum height its speed is zero. Therefore the final velocity term is zero.
[tex]0 = (20)^{2}-2*10*y\\20*y=400\\y=20 [m][/tex]
Another important fact is that the sign of gravitational acceleration was taken as negative, since it acts in the opposite direction to the movement of the stone.
Select the correct answer.
What happens when a negatively charged object A is brought near a neutral object B?
OA. Object B gets a negative charge.
OB. Object B gets a positive charge.
OC. Object B stays neutral but becomes polarized.
OD. Object A gets a positive charge.
O E.Object A loses all its charge.
Answer:
Option C.
Polarization takes place!
I need question 5 please and correct any others if they’re wrong
A 34.75 kg boulder is rolling down a hill. If, at one moment, the boulder has a momentum of 239.5 kg ⋅ m/s, what is its velocity at that time?
Answer:
Velocity = 6.89 m/s
Explanation:
The equation for momentum: [tex]Momentum=(Mass)(Velocity)[/tex]
Substitute the given information into the equation and solve for velocity.
[tex]239.5=34.75(Velocity)\\\frac{239.5}{34.75}=\frac{34.75(Velocity)}{34.75\\}\\6.89=Velocity[/tex]
Explain relative velocity with examples
Answer:
Velocity of the moving objects with respect to other moving or stationary object is called “relative velocity” and this motion is called “relative motion”.
Explanation:
For example, you are in a bus and it goes with the velocity of 50 m/s to the east, then a truck passes you with a velocity of 60m/s to the east.
A boy rubs two balloons against his sweater. One balloon acquires a charge of 3.0 E -6 C. The other balloon acquires a charge of 2.5 E -7 C. If the balloons are positioned 1 cm apart, what is the electrical force between them?
Answer:
67.5 N
Explanation:
From the question given above, the following data were obtained:
Charge 1 (q₁) = 3.0×10¯⁶ C
Charge 2 (q₂) = 2.5×10¯⁷ C
Distance apart (r) = 1 cm
Force (F) =?
Next, we shall convert 1 cm to m. This can be obtained as follow:
100 cm = 1 m
Therefore,
1 cm = 1 cm × 1 m / 100 cm
1 cm = 0.01 m
Thus, 1 cm is equivalent 0.01 m.
Finally, we shall determine the electrical force between the two points charges as follow:
Charge 1 (q₁) = 3.0×10¯⁶ C
Charge 2 (q₂) = 2.5×10¯⁷ C
Distance apart (r) = 0.01 m
Electrical constant (K) = 9×10⁹ Nm²C¯²
Force (F) =?
F = Kq₁q₂ / r²
F = 9×10⁹ × 3.0×10¯⁶ × 2.5×10¯⁷ / (0.01)²
F = 0.00675 / 0.0001
F = 67.5 N
Therefore, the electrical force between the two points charges is 67.5 N
Which of the following is a physical state of matter? *
A mass
B volume
C liquid
Which of the following electromagnetic waves has the shortest wavelength?
A. ultraviolet
B. light
С. microwave
D. X-ray
Answer: Not including gamma-rays, x-ray has the shortest wavelength,
Which of the following is NOT a benefit of dancing?
1. Improves balance and coordination.
2. Helps boost your mood.
3. Challenges your brain.
4. Isolates you from other people.
Answer:
4
Explanation:
Which formula is used to calculate the mass of an object if the force and acceleration are known?
Answer:
m=F/a so the second one
force÷ by acceleration
plzz help.me with both questions
Explanation:
Primary cell
1. They are non-rechargeable.
2. The energy density of primary cells is more.
3. The internal resistance of primary cells is more.
4. Example : Zinc-Carbon cell.
Secondary cells
1. They are rechargeable cells.
2. The energy density of secondary cells is less.
3. The internal resistance of secondary cells is less.
4. Example : Car batteries
Current :
The flow of electric charge per unit time is called electric current. It can be given by the formula as follows :
[tex]I=\dfrac{q}{t}[/tex]
The SI unit of electric current is Ampere.
1 Ampere is defined as the current that flows with the electric charge of one Coulomb per second (C/s).
Energy that depends upon object mass and object height.
Answer:
That is Gravitational potential energy.
When does an object falling vertically through the air reach terminal velocity?
(1 Point)
A: when the acceleration of the object becomes negative
B: when the acceleration of the object is equal to g
C:when the air resistance equals the weight of the object
D:when the air resistance is greater than the weight of the object
Answer:
a. when the acceleration of the objects become negative
A horse pulls a plow with a 242 N force for
61.7 m. How much work does the horse do?
A. 3.92 J
B. 180 J
C. 0.255 J
D. 14900 J
Answer: The answer is D
Explanation: i had the same question and i just guessed and got it first try
Answer:
Explanation:
its D i have all my notes here and the top person of me is right :)
We emphasize performance over participation well before kids' bodies, minds, and interests mature. And we tend to value the child who can help win games or whose families can afford the rising fees." Take some time to think through your answer.
Answer:
Yes.
Explanation:
Yes, we emphasize performance over participation of kids in a competition which causes negative effect on kid's personality. We also prefer those children whose families can afford the fees which is our big failure. We should emphasize participation over performance and prefer those child who has the ability to win the game instead of those who can afford the fees.
Which question characterizes relative motion problems that involve motor boats? a. If the width of the river is X meters wide, then how much time does it take the boat to travel shore to shore? c. Both a and b. b. What distance downstream does the boat reach the opposite shore? d. None of the above.
Answer:
that the correct one is C
Explanation:
In relative motion problems, in this case the boat and the river, with respect to the land and between them, the most common questions are:
* What is the time to cross the river
* How far down does the boat go
* What direction the boat must have to reach the opposite shore
examining the answers we see that the correct one is C
The model shows how solar-powered electric cars indirectly use energy from the Sun. Describe the energy transformations that you see.
Answer:
Radiant energy from the Sun is converted into electrical energy. Electrical energy is then converted into chemical energy. Chemical energy is then converted into electric energy for the motor. The motor converts electrical energy into mechanical energy and makes the car move.
Sun makes radiant energy > converted to electrical energy through solar panels > converted to chemical energy which is then stored in a battery for the motor > converted into mechanical energy to make the car move
Extra:
Look at the image below for a better understanding of the question. I hope this helps! :)
Source:
Edmentum Guided Notes
The energy transformations that can be seen in solar-powered electric cars :
Solar energy > electrical energy > chemical energy > mechanical energy.
What is solar-powered electric cars?
A solar electric car is one that is primarily or entirely powered by solar energy. Solar panels typically feature photovoltaic (PV) cells that convert solar energy directly into electric energy. The phrase "solar vehicle" typically implies that all or some of a vehicle's propulsion is powered by solar energy. Communications, controls, and other auxiliary operations might all be powered by solar energy.
In solar electric car, solar energy converted into electrical energy by photovoltaic (PV) cells. This energy is stored in battery in the form of chemical energy. When the car moves, this chemical energy transforms into mechanical energy.
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How does the antireflective coating applied to the protective glass on a solar cell maximize the energy absorbed by the solar cell?
A. It helps the glass transmit the energy
B. It helps the glass reflect the energy that hits it
C. It stops the top semiconductor layer from absorbing too much energy
D. It stops the bottom semiconductor layer from absorbing too much energy
Answer:
A
Explanation:
The antireflective coating applied to the protective glass on a solar cell maximize the energy absorbed by the solar cell as it helps the glass transmit the energy. The correct option is A.
The antireflective coating added to the protective glass of a solar cell is intended to reduce light reflection from the glass's surface.
More light may flow through the glass and reach the solar cell underneath it by decreasing reflections. This permits the solar cell to absorb more energy from the sun, increasing its efficiency in converting light into electricity.
The antireflective coating guarantees that a larger proportion of incident light is passed through the glass by decreasing reflection, allowing the solar cell to gather and use more energy.
Thus, the correct option is A.
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Imagine that person B is more massive than person A in the picture above. 3 points
If they push off of each other with the same amount of force, who will
have the greater acceleration? What law are you applying? Explain how
that law is being applied."
Answer:bight
Explanation:
how much power is used to move a 25 kg mass 8 meters in 15 seconds?
Answer:
Concept: Physics
Power is related to Work which we will find below[tex]work = f \times d[/tex]Note that force is a vector quantity that has magnitude and direction We have a mass of 25 kg and we want to know the force it exerts by newton's first law: 25 × 9.81 m/s^2 = 245 N Now we have our force and d 245 × 8 meters= 1960 J Power is represented in joules The equation for Power is [tex]p = \frac{w}{t} [/tex]Hence [tex] \frac{1960}{10} [/tex]So we get that P= 196 WCan someone do this pls! I’ll give you brainilest and all my points!
Answer:
15N South
Explanation:
It is 15N South because the two 15N cancel out each other and then you subtract 5N from the 20N and then you get left with 15N. and the 20N is bigger and it is going South.So the answer is 25N south.
Answer:
the answer would be 15N south
help plz will give brainliest and dont answer if u dont know
Answer:
is highly motivated
Explanation:
what is SI unit electric current ?
Answer:
the si unit of electric current is Ampere .the flow of charge in a close circuit is called electric current
PLEASE HURRY What is "a section of a chromosome that typically contains the code for a particular protein, which determines a specific trait" called?
heterozygous
genetics
species
gene
Answer:
It is a gene!!
Explanation:
It is because RNA is referred to as a gene. Genes are contained in chromosones.
The image shows a type of fault.
What stress causes this type of fault to form?
A. Compression
B. Gravity
C. Tension
D. Shearing
Answer:
D. Shearing
Explanation:
D. Shearing
The Answer is: Shearing
Sheila lives in the seashore community of Beachview. At 6:00 a.M. One morning, she noticed that the local ocean water was at high tide. At approximately noon that same day, she noticed the water was at low tide.
Answer:
hello your question is incomplete below is the complete question
Sheila lives in the seashore community of Beachview. At 6:00 a.m. one morning, she noticed that the local ocean water was at high tide. At approximately noon that same day, she noticed the water was at low tide.
Which of the following describes what caused the change in tides between 6:00 a.m. and noon that day
options :
A)The Earth revolved approximately 90° around the Sun, and the gravitational attraction between the Moon and Sun increased.
B)The Earth completed one full rotation (360°), and the gravitational attraction between the Moon and the Beachview area increased.
C)The Earth completed one full revolution around the Sun (360°), and the gravitational attraction between the Moon and Sun decreased.
D)The Earth rotated approximately 90°, and the gravitational attraction between the Moon and the Beachview area decreased.
answer :
The Earth rotated approximately 90°, and the gravitational attraction between the Moon and the Beachview area decreased. ( D )
Explanation:
The movement of the Earth in the Galaxy occurs in two ways
namely: Rotation and Revolution and each movement comes has an effect on the earth, also each movement has a time frame as well.
The complete rotation of the earth about its axis takes about 24 hours and this rotation brings about Night and day and it also causes the rise and fall of tides. while the Revolution of the earth round brings about different seasons and it takes about 365 days for a complete revolution of the earth round the sun.
hence the the change in tides between 6:00 a.m. and noon that day is caused by The Earth rotating approximately 90°, and the gravitational attraction between the Moon and the Beachview area decreased.
6. In baseball, a fastball takes about 1/2 second to reach the plate. Assuming that such a pitch is thrown horizontally, compare the distance the ball falls in the first 1/4 second with the distance it falls in the second 1/4 second.
Answer:
The ball falls 0.3 m in the first 1/4 seconds, and it falls 0.92 m in the second 1/4 second
Explanation:
Horizontal Launch
When an object is thrown horizontally with a speed v from a height h, it describes a curved path ruled exclusively by gravity until it eventually hits the ground.
To calculate the vertical distance (y) traveled by the object in terms of the time (t) we use:
[tex]\displaystyle y=\frac{g.t^2}{2}[/tex]
The fastball is thrown horizontally. The distance the ball falls in t=1/4 seconds = 0.25 seconds, is:
[tex]\displaystyle y_1=\frac{9.8*0.25^2}{2}[/tex]
[tex]\displaystyle y_1=0.30625\ m[/tex]
The distance the ball falls in t=1/2 seconds = 0.5 seconds is:
[tex]\displaystyle y_2=\frac{9.8*0.5^2}{2}[/tex]
[tex]\displaystyle y_2=1.225\ m[/tex]
The distance it falls in the second 1/4 second is:
[tex]y_2-y_1=1.225\ m-0.30625\ m[/tex]
[tex]y_2-y_1=0.91875\ m[/tex]
The ball falls 0.3 m in the first 1/4 seconds, and it falls 0.92 m in the second 1/4 second
Which event in a solar cell uses the photoelectric effect?
A. Electromagnetic waves act according to the wave model of light,
not the particle model.
B. Electromagnetic waves remove electrons from the transparent
glass on the top of the cell.
C. Electromagnetic waves strike a semiconductor, removing some of
its electrons, which form a current.
D. Electrons flow from the negatively charged semiconductor to the
positively charged one.
Answer:C
Explanation: yea
Electromagnetic waves striking a semiconductor, removing some of its electrons, and forming a current is an event in a solar cell which uses
What are electromagnetic waves?
The electromagnetic radiation consists of waves made up of electromagnetic field which are capable of propogating through space and carry the radiant electromagnetic energy.
The radiation are composed of electromagnetic waves which are synchronized oscillations of electric and magnetic fields . They are created due to change which is periodic in electric as well as magnetic fields.
In vacuum ,all the electromagnetic waves travel at the same speed that is with the speed of air.There are 7 types of electromagnetic waves in the electromagnetic spectrum.These have different wavelength, frequency and energy.
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Sam scored 98, 25, 105, 62 and 65 runs in 5 matches. What was the average score per match?
Answer:
71
Explanation:
Why is a protective apron or lab coat important to use when working with acids?
Acids conduct electricity and contact could cause a shock.
Acids react with lipids and can cause damage to skin tissue.
Acids break down fabrics and can cause burns if the acids are strong.
Acids have a slippery feel and could result in a fall.
Answer:
Acids break down fabrics and can cause burns if the acids are strong.
Explanation:
When working with acids, it is advisable for a scientist for wear a protective apron or lab coat because acids break down fabrics and can cause burns.
Acids are chemical substances that produces excess hydroxonium ions in solutions.
Due to their unique properties they are highly corrosive and are used to remove rusts from any surface. We they come in contact with the human body, they can cause severe burns especially if they are very strong acid. If an apron is worn, then the body will be shielded.Answer:
C. Acids break down fabrics and can cause burns if the acids are strong.
Explanation:
i did the quiz on edg
How are mass and volume alike?
They always stay the same
They are both measured in grams
The cease to exist when placed in a liquid
Answer:
its b
Explanation:
b