Answer:
The initial speed of the sprinter was 2.2 m/s
Explanation:
Constant Acceleration Motion
It's a type of motion in which the velocity of an object changes by an equal amount in every equal period of time.
The following relation applies:
[tex]v_f=v_o+at[/tex]
Where a is the constant acceleration, vo the initial speed, vf the final speed, and t the time.
The sprinter speeds up from an unknown initial speed to vf=3 m/s in t=2 seconds with an acceleration of [tex]a=0.4~m/s^2[/tex].
To find the initial speed, we solve the equation for vo:
[tex]v_o=v_f-at[/tex]
Substituting the values:
[tex]v_o=3-0.4*2[/tex]
[tex]v_o=3-0.8[/tex]
[tex]v_o=2.2~m/s[/tex]
The initial speed of the sprinter was 2.2 m/s
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Answer:
koj ruam zog
Explanation:
Answer:
the answer of 7th question
Make sure your dishwasher is full before you use it – running a half-empty dishwasher wastes large amounts of energy
Try to use a cooler temperature
Consider drying your clothes outside if it’s warm instead of using the dryer
Turn off the fan when you leave a room
Close your drapes or drop your window shades during the day.
Wash your clothes in cold water.
Wrap or cover foods and drinks in the refrigerator.
Always use the cold water faucet, unless you really want hot water.
the answer of 10th question
Static electricity is used in pollution control by applying a static charge to dirt particles in the air and then collecting those charged particles on a plate or collector of the opposite electrical charge. These devices are commonly known as “electrostatic precipitators.
Snails crawl very slowly. If a garden snail crawls at 0.013 m/s north, how far will it travel in 60 seconds?
Answer:
.78 m/s north
Explanation:
Pls give brainliest if I correct
brainlists please help
on the coner opposite of 8n is 5n
Answer:
resultant force=16N→(TOWARDS THE DIRECTION OF 8N)
Explanation:
resultant force=8N+13N-5N
=16N→(TOWARDS THE DIRECTION OF 8N)
To illustrate the use of a multistage rocket consider the following:
(a) A certain rocket carries 60% of its initial mass as fuel. (That is, the mass of fuel is 0.6mo) What is the rocket's final speed, accelerating from rest in free space, if it burns all its fuel in a single stage? Express your answer as a multiple of v ex .
(b) Suppose instead it burns the fuel in two stages as follows: In the first stage it burns a mass 0.3m o of fuel. It then jettisons the first-stage fuel tank, which has a mass of 0.1m o , and thenburns the remaining 0.3m 0 of fuel. Find the final speed in this case, assuming the same value of vex throughout and compare.
Answer:
a
[tex]v_f = 0.916 v_{ex}[/tex]
b
[tex]v_f = 1.05 v_{ex}[/tex]
Explanation:
Considering question a
From the question we are told that
The mass of the rocket is [tex]m_o[/tex]
The mass of the fuel which is in the rocket is m = 0.6 M
Generally given that the rocket burns all it fuel in a single stage , the final velocity of the rocket is mathematically represented as
[tex]v_f = v_{ex} ln [\frac{m_o}{m_k} ][/tex]
Here [tex]m_k[/tex] is the mass of the rocket without fuel which is mathematically evaluated as
[tex]m_k = m_o- m[/tex]
=> [tex]m_k = m_o -0.6m_o[/tex]
=> [tex]m_k = [1- 0.6] m_o[/tex]
=> [tex]v_f = v_{ex} ln [\frac{m_o}{[1 - 0.6]m_o} ][/tex]
=> [tex]v_f = 0.916 v_{ex}[/tex]
Considering question b
From the question we are told that
The mass of the fuel it burn at the first stage is [tex]m = 0.3 m_o[/tex]
The mass of the first stage fuel tank [tex]m_1 = 0.1 m_o[/tex]
The mass of the fuel at the second stage is [tex]m_f = 0.3m_o[/tex]
Generally the velocity of the rocket at the first stage is mathematically represented as
[tex]v_i = v_{ex} * ln [ \frac{m_o }{[1- m]m_o } ][/tex]
=> [tex]v_i = v_{ex} * ln [ \frac{m_o }{[1- 0.3]m_o } ][/tex]
=> [tex]v_i = v_{ex} * ln [ \frac{1 }{0.7 } ][/tex]
=> [tex]v_i =0.357 v_{ex}[/tex]
Generally the mass of the rocket after first stage is
[tex]m_r = m_o - 0.3m_o -0.1m_o[/tex]
=> [tex]m_r = 0.6m_o[/tex]
Generally the final velocity of the rocket at the second stage is
[tex]v_f = v_i + v_{ex} * ln [\frac{m_r}{ m_f } ][/tex]
=> [tex]v_f = v_i + v_{ex} * ln [\frac{0.6 m_o }{0.3mo } ][/tex]
=> [tex]v_f = 0.357 v_{ex} + 0.693 v_{ex}[/tex]
=> [tex]v_f = 1.05 v_{ex}[/tex]
Current 1 of 8.4 A runs for 240 seconds and then stops. Current 2 is 10.5 A. How long does current 2 have to run to deliver the same amount of charge as current 1?
This question involves the concepts of current and charge.
Current 2 has to run for "192 s" to deliver the same amount of charge as current 1.
CurrentThe current is defined as the amount of charge passing per unit time. Mathematically,
[tex]I=\frac{q}{t}\\\\q = It[/tex]
Since, the charge for both the currents is same:
q₁ = q₂
I₁t₁ = I₂t₂
[tex]t_2=\frac{I_1t_1}{I_2}[/tex]
where,
I₁ = current 1 = 8.4 A
I₂ = current 2 = 10.5 A
t₁ = time for current 1 = 240 s
t₂ = time for current 2 = ?
Therefore,
[tex]t_2=\frac{(8.4\ A)(240\ s)}{10.5\ A}[/tex]
t₂ = 192 s
Learn more about charges here:
https://brainly.com/question/19886264
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How do the prefixes micro,
nano and pico relate to each
other?
Answer:
because they are same and their properties
Which quantity is a vector quantity?
А.
acceleration
B.
mass
C.speed
D.
volume
Answer:
acceleration .......
A motorcyclist drives around a bend with a 20 m radius, with a constant velocity of 3 m/s. The motorcyclist and the motorcycle have a combined mass of 50 kg. What is the motorcyclist’s centripetal acceleration?
Answer:
[tex]a=0.45\ m/s^2[/tex]
Explanation:
Given that,
The radius of a bend, r = 20 m
Velocity of motorcyclist, v = 3 m/s
The combined mass of motorcyclist and the motorcycle is 50 kg
We need to find the motorcyclist’s centripetal acceleration. The formula used to find the centripetal acceleration is given by :
[tex]a=\dfrac{v^2}{r}\\\\a=\dfrac{(3)^2}{20}\\\\a=0.45\ m/s^2[/tex]
So, the acceleration of the motorcyclist is [tex]0.45\ m/s^2[/tex].
4. What is the speed of a walking person in m/s if the person travels 1000m in 20 minutes?
Answer:
0.80 m/s
Explanation:
What is the speed of a walking person in m/s if the person travels 1000 m in 20 minutes?
help me pleaseeeee
Answer:
Explanation:
Frequency, in physics, the number of waves that pass a fixed point in unit time; also, the number of cycles or vibrations undergone during one unit of time by a body in periodic motion...............
What happens along a divergent boundary?
Answer:
Two tectonic plates move away from each other
Explanation:
I just did this on AP3X. If this is not what your lookinf for then so sorry
Please simplify and write the below paragraph.
The field lines due to a current in a
circular coil become straight and
perpendicular to the plane of the coil
at the centre. This is because at every
point of circular loop the concentric
circles representing the magnetic field
become larger and larger as we move
away from the wire.
Field lines become straight and perpendicular because every point of circular loop the concentric circles become larger and larger as we move away from the wire.
An automobile travels a displacement of 75 km at 45 degrees north of East. How many kilometers north does it travel?
Answer:
the number of kilometers north it traveled is 53.03 km
Explanation:
The computation of the number of kilometers north it traveled is shown below:
Given that
The Displacement of 75 km
At east north of 45 degrees
Based on the above information, the number of kilometers is
= 75 × cos 45
= 53.03 km
Hence, the number of kilometers north it traveled is 53.03 km
We simply applied the above formula so that the correct value could come
And, the same is to be considered
Which of the following statement(s) about electrical charges are correct?
A. Point charges of the same charge only attract.
B. Charged and neutral extended objects can attract.
C. Charged and neutral extended objects do not interact.
D. Point charges of the same charge only repel.
E. Extended objects of opposite charge can only attract.
F. Point charges of opposite charge only attract.
G. Point charges of opposite charge only repel.
H. Extended objects of the same charge can both repel and attract.
I. Extended objects of the same charge can only attract.
J. Extended objects of the same charge can only repel.
K. Extended objects of opposite charge can both repel and attract.
Answer:
The true statements are;
F, D, E, J
Explanation:
F and D are true because they agree with our knowledge of electrostatic interaction. Like charges repel while unlike charges attract. Statements B and C are not in line with the principles of electrostatics because neutral objects do not interact with charged bodies in an electric field.
E and J are true for the same reasons outlined above. Remember that like charges always repel each other and unlike charges always attract each other.
HELP ME! PLEASE! SOMEONE! THIS QUESTION IS VERY HARD! THERE ARE 3 ANSWERS! HELP ME PLEASE! MAKE SURE TO EXPALIN
Question:
The teacher told Fatima that all types of energy are kinetic energy, potential energy, or both. Fatima drew this diagram to help her organize this information. She then sorted each type of energy into its correct category: chemical, electrical, electromagnetic, mechanical, nuclear, and thermal.
Three of the types of energy can be either kinetic or potential energy. Identify these three types. For each type, explain why it can be either kinetic or potential.
Answer:
search up the kinetic energy and potential energy etc. then take them and look at the characteristica are they the same? What makes them similar? Why are they different ? How? Then add the chemical nuclear and electrical changes it creates. Now the rest! There you’ve got this! If you need support I’m here! Hope this helped!
Explanation:
which term describes the image of an object that is placed in front o a convex mirror?
Answer:
The answer of this question is :- Virtual image
Explanation:
Virtual image is the correct answer
What is the density of a piece of quartz with a mass of 30g and a volume of 6cm^3
Answer:
[tex]\boxed {\boxed {\sf d= 5 \ g/cm^3}}[/tex]
Explanation:
Density can be found by dividing the mass by the volume.
[tex]d=\frac{m}{v}[/tex]
The mass of the quartz is 30 grams and the volume is 6 cubic centimeters.
[tex]m=30 \ g \\v= 6 \ cm^3[/tex]
Substitute the values into the formula.
[tex]d=\frac{30 \ g}{6 \ cm^3}[/tex]
Divide.
[tex]d= 5 \ g/cm^3[/tex]
The density of this piece of quartz is 5 grams per cubic centimeter.
observe the figure given carefully volume of water in each vessel is shown arrange them in order of decreasing pressure at the base of each vessel explain the reason
Answer:
See the explanation below
Explanation:
The pressure is defined as the product of the density of the liquid by the gravitational acceleration by the height, and can be easily calculated by means of the following equation.
[tex]P=Ro*g*h[/tex]
where:
Ro = density of the fluid [kg/m³]
g = gravity acceleration = 9.81 [m/s²]
h = elevation [m]
In this way we can understand that the greater pressure is achieved by means of the height of the liquid, that is, as long as the fluid has more height, greater pressure will be achieved at the bottom.
Therefore in order of decreasing will be
The largest pressure with the largest height of the liquid, container B. The next is obtained with container D, the next with container A and the lowest pressure with container C.
The pressure decreases as we go from the container B - D - A - C
Use the diagram to answer the questions below.
1. What is the relationship between seasons in the northern hemisphere and southern hemisphere? Explain.
2. Identify the seasons that are represented in the northern hemisphere and in the southern hemisphere. Explain.
Answer:
1. because of the tilted axis of earth the seasons in northern hemisphere are the exact opposite of the southern. because the sunrays reaches the earth an different points and when the earth moves around the sun it changes the hemisphere which is tilted to the sun.
2. the northern hemisphere is in Winter and the southern in summer. because the southern is tilted to the sun and the northern not so less sunrays reaches the northern hemisphere.
I'm sorry my explanation are bad
During combustion reactions, explain why the energy of the reactants must exceed the total energy of the products
Answer:
In these reactions the products are higher in energy than the reactants. ... This barrier is due to the fact that to make CO2 and H2O we have to break 4 carbon-hydrogen bonds and some ...
Explanation:
We do not use water instead of mercury in a barometer.. why.
Answer:
Required Answer:-We don't use water as Water don't expand when it came in connection of temperature.A stone is thrown straight up. While the stone is rising:
A. its acceleration is upward and decreasing
B. its acceleration is upward and constant
C. its acceleration is upward and increasing
D. its acceleration is zero
E. None of the above.
Answer:
D. its acceleration is zero
Explanation:
Acceleration can be defined as the rate of change of the velocity of an object with respect to time.
This simply means that, acceleration is given by the subtraction of initial velocity from the final velocity all over time.
Hence, if we subtract the initial velocity from the final velocity and divide that by the time, we can calculate an object’s acceleration.
Mathematically, acceleration is given by the equation;
[tex]Acceleration (a) = \frac{final \; velocity - initial \; velocity}{time}[/tex]
In this scenario, a stone is thrown straight up. While the stone is rising its acceleration is zero because it's initial velocity is zero and it's until the stone reaches its highest point before the acceleration becomes constant and acting downward.
The lift goes up 14m the total mass of the people is 280kg
Answer:
What is your Question.
Explanation:
Ask it Clearly.
Your car is initially at rest when you hit that gas and the car begins to accelerate. The forward force of the car is 5630 N while the resisting force total 330 N. The car has a mass of 1313 kg and the acceleration lasts for 2.6s. What is the final speed of the car and how much ground does it cover during this acceleration?
Chuck Is driving from Chicago to Miami, in one hour he drives 120 km. What is Chuck’s average velocity?
Answer:
Chuck's average speed is 60.
How are speed and velocity alike?
A.) They both require a reference point
B.) They both include total distance traveled
C.) They both describe a rate of motion
D.) They both include the direction of motion
Answer:
im pretty sure B
Explanation:
Answer:
B
Explanation:
They both describe a rate of motion
What is one of the principles of charges in a conductor?
Answer:
A conductor allows free charges to move about within it. The electrical forces around a conductor will cause free charges to move around inside the conductor until static equilibrium is reached. Any excess charge will collect along the surface of a conductor. Conductors with sharp corners or points will collect more charge at those points.
Explanation:
PLEASE HELP!!!!!!
A box is dragged across a floor. The box accelerates at 0.09 m/s² and is pulled by a 75 N force. What is the mass of the box?
833 kg
12 g
833 g
6.75 kg
Answer:833
Explanation:
A mineral:__________
a) must have an identifiable chemical composition.
b) This includes solids with a compositions that can be identified but not expressed by an exact chemical formula; an example is glass must be inorganic.
c) This excludes the vast number of organic compounds produced by living matter. must be naturally formed or formed from naturally occuring compounds.
d) This includes the vast numbers of substances that can be produced in a laboratory but are not found in nature. must be a solid or a liquid.
e) This excludes all gases.
Answer:
The correct options are A, B, C and E
Explanation:
The above speaks to the characteristics of Minerals.
Option D is excluded because minerals cannot be liquid or gaseous. Even if it is possible, those replicated in the laboratory are not considered as minerals neither are minerals liquid. They must be solid. The molecules for most minerals are very tightly or densely arranged because of the nature of their formation. Most of them are formed under consistent and intense pressure.
Cheers!
5. One of the attractions at Typhoon Lagoon, a water park in Florida, is a surf
pool. 303,200.0 liters of water are used for each wave in the surf pool and
waves are generated every 90 seconds. How many gallons of water are used
every 30 minutes in the surf pool.?
Answer:
1595790 gallons
Explanation:
Given that;
3.8 L = 1 US gallon
303,200.0 liters = 303,200.0 * 1/ 3.8 = 79789.5 gallons
If a wave is made every 90 seconds which is 1.5 mins
Then;
Number of waves made in 30 minutes = 30/1.5 = 20 waves
if each uses 79789.5 gallons, then 20 waves will use 20 * 79789.5 gallons = 1595790 gallons