At t = 0, Ball 1 is dropped from the top of a 22 m-high building. At the same instant Ball 2 is thrown straight up from the base of the building with an initial velocity of +12 m/s. Assume that Ball 1 starts from rest and that air friction can be ignored. At what height will the two balls pass each other? What is the velocity of each ball at the moment they are at the same height?

Answers

Answer 1

Answer:

The two balls pass each other at a height of 5.53 m

vf1=17.97 m/s

vf2=-5.96 m/s

Explanation:

Vertical Motion

An object thrown from the ground at speed vo, is at a height y given by:

[tex]y=vo.t-g.t^2/2[/tex]

Where t is the time and [tex]g=9.8\ m/s^2[/tex]

Furthermore, an object dropped from a certain height h will fall a distance y, given by:

[tex]y=g.t^2/2[/tex]

Thus, the height of this object above the ground is:

[tex]H = h-g.t^2/2[/tex]

The question describes that ball 1 is dropped from a height of h=22 m. At the same time, ball 2 is thrown straight up with vo=12 m/s.

We want to find at what height both balls coincide. We'll do it by finding the time when it happens. We have written the equations for the height of both balls, we only have to equate them:

[tex]vo.t-g.t^2/2=h-g.t^2/2[/tex]

Simplifying:

[tex]vo.t=h[/tex]

Solving for t:

[tex]t=h/vo=22/12=1.833\ s[/tex]

The height of ball 1 is:

[tex]H = 22-9.8.(1.833)^2/2[/tex]

H = 5.53 m

The height of ball 2 is:

[tex]y=12\cdot(1.833)-9.8\cdot(1.833)^2/2[/tex]

y=5.53 m

As required, both heights are the same.

The speed of the first ball is:

[tex]vf1=g.t=9.8\cdot 1.833=17.97\ m/s[/tex]

vf1=17.97 m/s

The speed of the second ball is:

[tex]vf2=vo-gt=12-9.8\cdot 1.833=-5.96\ m/s[/tex]

vf2=-5.96 m/s

This means the second ball is returning to the ground when both balls meet


Related Questions

The ratio of carbon-14 to nitrogen-14 is an artifact is 1:3. Given that half-life of carbon-14 is 5730years, how old is the artifact?

Answers

Answer:

9155 years old

Explanation:

We use the following expression for the decay of a substance:

[tex]N = N_0\,\,e^{-k*t}[/tex]

So we first estimate the value of k knowing that the half-life of the C14 is 5730 years:

[tex]N = N_0\,\,e^{-k*t}\\N_0/2=N_0\,\,e^{-k*5730}\\1/2 = e^{-k*5730}\\ln(1/2)=-k*5730\\k= 0.00012[/tex]

so, now we can estimate the age of the artifact by solving for"t" in the equation:

[tex]1/3=e^{-0.00012*t}\\ln(1/3)= -0.00012*t\\t=9155. 102[/tex]

which we can round to 9155 years old.

what is the diffrence between scalar and vector physical quantites write all examples that you know about each of them​

Answers

Answer:

Scalar quantity is defined as the physical quantity with magnitude and no direction.

There are plenty of scalar quantity examples, some of the common examples are:

Mass

Speed

Distance

Time

Area

Volume

Density

Temperature

A vector quantity is defined as the physical quantity that has both direction as well as magnitude.

Vector quantity examples are many, some of them are given below:

Linear momentum

Acceleration

Displacement

Momentum

Angular velocity

Force

Electric field

Polarization

) The square plates of a 5000-pF parallel-plate capacitor measure 50 mm by 50 mm and are separated by a dielectric that is 0.23 mm thickand totally fills the region between the plates. The voltage rating (the maximum safe voltage) of the capacitor is 400 V. What is the maximum energy that can be stored in this capacitor without damaging it

Answers

Answer:

4 x 10⁻⁴ J

Explanation:

C = 5000 pF, V = 400 V

Energy = CV²/2 = 5000 x 10⁻¹² x 400²/2 = 4 x 10⁻⁴ J

If you were to pour 4 different liquids into a glass and the liquids separated into 4 layers, which liquid would have the highest density?
A. the layer at the bottom of the glass
B. the third layer from the bottom of the glass
C. the layer at the top of the glass
D. the second layer from the bottom of the glass

Answers

Answer:

A.

Explanation:

The liquid with the higher density will be found at the bottom of the glass because is the heaviest of all. The liquids which have a lower density than the liquid at the bottom of the glass will be found at the top of the glass. We assume that the liquids are not soluble in each other because otherwise they will be mixed.

a strong inductive argument must have true premises

True

False

Answers

That is true imo not false

A 6.0 kg object is moving at 5.0 m/s along the x axis in the positive direction. It collides
with and sticks to a 2.0 kg object moving also along the x axis. After the collision the
composite object is moving 2.0 m/s along the x axis in the negative direction.
Determine the velocity (magnitude and direction) of the 2.0 kg object before the collision.

Answers

Answer:

V2 =  23 [m/s] to the left.

Explanation:

In order to solve this problem, we must use the definition of conservation of linear momentum. That is, the momentum is conserved before and after the collision. The values before the collision will be taken to the left of the equality, and the values after the collision will be taken to the right of the equality, in this way we have:

Σbefore = Σafter

ΣPbefore = ΣPafter

where:

P = m*v

The positive momentum will be taken to the right and the negative momentum is to the left in this way we formulate the following equation:

[tex](m_{1}*v_{1}) + (m_{2}*v_{2})=-(m_{1} +m_{2})*v_{3}\\[/tex]

where:

m1 = mass of the first object = 6 [kg]

v1 = velocity of the first object = 5 [m/s]

m2 = mass of the stick = 2 [kg]

v2 = velocity of the stick [m/s]

v3 = velocity of the composite object = - 2 [m/s]

(6*5) + (2*V2) = - (6 + 2)*2

30 + (8*2) = - 2*V2

46 = - 2*V2

V2 = - 23 [m/s]

Note: the negative sign means the stick moves to the left

Which of the following is a description of the Remote Associates Test (RAT)?

Answers

Answer:

The description is outlined throughout the clarification section following, and according to the given word.

Explanation:

Throughout the 1960s, Sarnoff Mednick created the RAT as a tool used for testing imaginative convergent thought. Through each RAT test query lists a set of terms, which demands that we have a single additional term that will tie any of the others around.  Those other words may also be related in something like a variety of ways, such as through creating a compound word or perhaps a semantic connexon.

describe an example that shows thermal energy cannot be stored for a long time​

Answers

Answer: heat always flows from higher temperature to lower temperature

Explanation: there:)

Heat always flows from higher temperature to lower temperature so can not be stored.

What is  thermal energy?

The energy present in a system that determines its temperature is referred to as thermal energy. Thermal energy flows as heat. Thermodynamics is a whole field of physics that studies how heat is transmitted across various systems and how work is performed in the process.

Heat dissipation always happen decrease in temperature so thermal energy can not be stored for long time.

Heat always flows from higher temperature to lower temperature so can not be stored

To learn more about thermal energy refer to the link:

brainly.com/question/13552918

#SPJ2

Two insulated copper wires of similar overall diameter have very different interiors. One wire possesses a solid core of copper, with a circular cross section of radius 1.53 mm. The other wire is composed of 19 strands of thin copper wire bundled together. Each strand has a circular cross section of radius 0.306 mm. The current density ???? in each wire is the same. ????=1750 A/m2 Two circles. One circle is solid, whereas the other contains 19 tightly packed smaller circles How much current does each wire carry? solid wire current: A stranded wire current: A The resistivity of copper is ????=1.69×10−8 Ω·m. What is the resistance of a 3.25 m length of each wire? solid wire resistance: Ω stranded wire resistance: Ω

Answers

Answer:

a

 Solid Wire     [tex]I  =   0.01237 \  A [/tex]      

  Stranded  Wire  [tex]I_2  =   0.00978 \  A [/tex]

b

  Solid Wire   [tex]R  = 0.0149 \ \Omega [/tex]

   Stranded  Wire  [tex]R_1  = 0.0189 \ \Omega [/tex]

Explanation:

Considering the first question

From the question we are told that

  The  radius of the first wire is  [tex]r_1  = 1.53 mm = 0.0015 \  m[/tex]

  The radius of  each strand is  [tex]r_0 =  0.306 \ mm =  0.000306 \ m[/tex]

  The current density in both wires is  [tex]J  =  1750 \  A/m^2[/tex]

Considering the first wire

     The  cross-sectional area of the first wire is

      [tex]A   = \pi  r^2[/tex]

= >  [tex]A   = 3.142 *  (0.0015)^2[/tex]

= >  [tex]A   = 7.0695 *10^{-6} \  m^2 [/tex]

Generally the current in the first wire is    

     [tex]I  =  J*A[/tex]

=>  [tex]I  =  1750*7.0695 *10^{-6}[/tex]

=>  [tex]I  =   0.01237 \  A [/tex]

Considering the second wire  wire

The  cross-sectional area of the second wire is

     [tex]A_1  =  19 *  \pi r^2[/tex]

=>     [tex]A_1  =  19 *3.142 *  (0.000306)^2[/tex]

=>  [tex]A_1  =  5.5899 *10^{-6} \  m^2[/tex]

Generally the current is  

      [tex]I_2  =  J  *  A_1[/tex]

=>    [tex]I_2  =   1750  *  5.5899 *10^{-6} [/tex]

=>    [tex]I_2  =   0.00978 \  A [/tex]

Considering question two  

 From the question we are told that

     Resistivity is  [tex]\rho  =  1.69* 10^{-8} \Omega \cdot m[/tex]

     The  length of each wire  is  [tex]l =  6.25 \  m[/tex]

Generally the resistance of the first wire is mathematically represented as

    [tex]R  =  \frac{\rho *  l  }{A}[/tex]

=> [tex]R  =  \frac{  1.69* 10^{-8} * 6.25 }{ 7.0695 *10^{-6} }[/tex]

=> [tex]R  = 0.0149 \ \Omega [/tex]

Generally the resistance of the first wire is mathematically represented as

    [tex]R_1  =  \frac{\rho *  l  }{A_1}[/tex]

=> [tex]R_1  =  \frac{  1.69* 10^{-8} * 6.25 }{5.5899 *10^{-6} }[/tex]

=> [tex]R_1  = 0.0189 \ \Omega [/tex]

A block is 10cm long, 5cm wide and 2cm high and weighs 100g. What is the volume of the block? What is the density?

Answers

Answer:

1gm/cm^3

Explanation:

its the answer

we can see objecf in bright room because​

Answers

Answer:

because there is a reflection due to light in the the room.

Explanation:

if if it's helped you please mark as brainliest and like and follow please

We can see objects in a bright room because, the object reflect the light falling on them

e.) calculate the total heat required to change 10kg of ice at 0°c into water at 50°c. ​

Answers

Answer:

the heat change to 10kg of ice to water 0

so quantity of heat required is answer: 5460 J.

hope its helps!

Answer:

Q=ml+mc∆+ml'

=10*80+10*1*(100-0)+10*540

=800+1000+5400

=7200cal.7.2kcel

L=heat of fusion of ice

L'=heat of vapourisation of water

If object A exerts a force on another body B, then body B exerts an equal and opposite for on body A. Which newton is this?

Answers

Answer:

newton 's 3rd law which states that to every action there's equal but opposite reaction

Amoving object is in equilibrium. Which best describes the motion of the object if no forces change?
a. It will change directions.
b. It will slow down and stop.
c. It will maintain its state of motion.
d. It will speed up and then slow down.​

Answers

I think the answer is c

If electrons are added to an object the object becomes
charge.
negative
positive
neutral
nothing happens

Answers

Answer:

It can be either, depending on how much and how you add the electrons

2.27 A gas is compressed from V1= 0.3 m3, p1=1 bar to V2= 0.1 m3, p2 =3 bar. The pressure and
the volume are related linearly during the process. For the gas, find the
work, in kJ.
2.29 A gas expands from an initial state where p1=500kPa and V1=0.1m3 to a state
end where p2= 100 kPa. The relationship between pressure and volume during the process is
pV=constant. Schematize the process in a p-V diagram and determine the work, in
kJ.

Answers

Answer:

-40 kJ

80 kJ

Explanation:

Work is equal to the area under the pressure vs volume graph.

W = ∫ᵥ₁ᵛ² P dV

2.27) Pressure and volume are linearly related.  When we graph P vs V, the area under the line is a trapezoid.  So the work is:

W = ½ (P₁ + P₂) (V₂ − V₁)

W = ½ (100 kPa + 300 kPa) (0.1 m³ − 0.3 m³)

W = -40 kJ

2.29) Pressure and volume are inversely proportional:

pV = k

The initial pressure and volume are 500 kPa and 0.1 m³.  So the constant is:

(500) (0.1) = k

k = 50

The final pressure is 100 kPa.  So the final volume is:

(100) V = 50

V = 0.5

The work is therefore:

W = ∫ᵥ₁ᵛ² P dV

W = ∫₀₁⁰⁵ (50/V) dV

W = 50 ln(V) |₀₁⁰⁵

W = 50 (ln 0.5 − ln 0.1)

W ≈ 80 kJ

what is E=mc^2?
please explain..

Answers

Answer:

In physics, mass–energy equivalence is the principle that anything having mass has an equivalent amount of energy and vice ve

The potential energy stored in the compressed spring of a dart gun, with a spring constant of 32.50 N/m, is 0.640 J. Find by how much is the spring is compressed. Submit Answer Tries 0/20 A 0.050 kg dart is fired straight up. Find the vertical distance the dart travels from its position when the spring is compressed to its highest position. Submit Answer Tries 0/20 The same dart is now fired horizontally from a height of 3.90 m. The dart remains in contact until the spring reaches its equilibrium position. Find the horizontal velocity of the dart at that time. Submit Answer Tries 0/20 Find the horizontal distance from the equilibrium position at which the dart hits the ground.

Answers

Answer:

A

   [tex]x = 0.198456 \ m [/tex]

B

    [tex]h  =  1.3061 \  m  [/tex]

C

 [tex]  v =  5.06 \  m/s [/tex]

D

  [tex]d = 4.0273 \  m  [/tex]

Explanation:

Considering the first question

From the question we are told that

   The spring constant is  [tex]k  =  32.50 N/m[/tex]

    The potential energy is  [tex]PE  =  0.640 \ J[/tex]

Generally the potential  energy stored in spring  is mathematically represented as   [tex]PE  =  \frac{1}{2}  *  k  *  x^2[/tex]

=>    [tex]0.640=  \frac{1}{2}  * 32.50  *  x^2[/tex]  

=>    [tex]x = \sqrt{0.03938}[/tex]  

=>    [tex]x = 0.198456 \ m [/tex]  

Considering the second question

 From the question we are told that

   The mass of the dart is  m =  0.050 kg

Generally from the law of energy conservation

         [tex]PE =  mgh[/tex]

=>       [tex]0.640   =  0.050 *  9.8  *  h[/tex]

=>      [tex]h  =  1.3061 \  m  [/tex]

Considering the third  question

   The height at which the dart was fired horizontally is  [tex]H  =   3.90\  m[/tex]

Generally  from the law of energy conservation

         [tex]PE = KE [/tex]

Here  KE is kinetic energy of the dart which is mathematical represented as

     [tex]KE  =  \frac{1}{2}  *  mv^2[/tex]

=>      [tex]0.640 =  \frac{1}{2}  * 0.050 *  v^2 [/tex]

=>       [tex]  v^2 = 25.6 [/tex]

=>       [tex]  v =  5.06 \  m/s [/tex]

Considering the fourth question

Generally the total time of flight of the dart is mathematically represented as

       [tex]t  =  \frac{ 2 *  H }{g}[/tex]

=>     [tex]t  =  \frac{ 2 * 3.90 }{9.8 }[/tex]

=>     [tex]t  =  0.7959 \ s [/tex]

Generally the  horizontal distance from the equilibrium position to the ground is  mathematically represented as

       [tex]d =  v  *   t[/tex]

=>     [tex]d = 5.06  *   0.7959[/tex]

=>     [tex]d = 4.0273 \  m  [/tex]

Lana's class is studying the various kinds of energy found on a playground
Which of the following would be the BEST way to test for an equal transformation of energy on a playground?
СА
Using the slide, Lana could measure her kinetic energy when she was climbing up the ladder, measure her potential energy before she slid down, and her total energy used at the bottom of the slide. If the amount of potential
energy and kinetic energy added up to equal the total amount of energy used, it would show an equal transformation of energy
OB
Using the slido, Lana could measure her potential and kinetic energy sitting at the top of the slide, and then she could measure her kinetic and potential energy at various points while sliding to the bottom of the total value of
her potential energy and her kinetic energy were equal at every measuremont, it would show that there had been an equal transformation
C
Using the swing, Lana could measure her potential energy when she was sitting still on the swing, and she could measure her kinetic energy when the swing was in motion. If the kinetic energy was twice the amount of her
potential energy, it would show there had boon an equal transformation of potential energy to kinetic energy
D
Using the soesaw, Lana could measure her potential energy when she was in motion, and she could measure her kinetic energy when she was resting. If her kinetic and potential energy were equal, it would show that there
had been an equal transformation

Answers

If the amount of potential energy and kinetic energy added up to equal the total amount of energy used, it would show an equal transformation of energy.

What is Energy?

This can be defined as the ability or capacity to do work. The potential and kinetic energy equals the total amount of energy involved when Lana was on the playground.

This depicts an equal transformation of energy which is why the most appropriate choice in this scenario is option A.

Read more about Energy here  https://brainly.com/question/582060

5
Find the resultant of the following four forces.
A= 25 N due north
B = 50 N due east
C= 30 N due west
D=40 N due south

Answers

25+50-30-40 = 0

north and east are positive directions, south and west are negative

hope this helps

also hope u enjoy a pic of my crush lol

Define kinetic Energy and thermal energy. Describe what happens to each as the temperature of a substance is increases.

Answers

Explanation:

Kinetic energy is the energy by virtue of

object's motion whereas Thermal energy is

the internal energy of an object due to the

kinetic energy of its atoms.

On Increasing temperature, they both

increases

Question 4
5 pts
What is microscopic and floats in the ocean?
Plankton
Benthos
Nekton
© Fish

Answers

Answer:

Plankton is the correct answer I think

Why is a very small fraction (0.001%) of the water found in the atmosphere?

Answers

There is a very small fraction (0.001%) of the water found in the atmosphere due to evaporation of water.

What is Atmosphere?

This is defined as mixture of gases surrounding the Earth or other celestial body, held in place by gravity.

A very small fraction (0.001%) of the water in the form of water vapor gas exist in the atmosphere due to evaporation by heat from the Sun.

Read more about Atmosphere here https://brainly.com/question/24925283

How far away is the light away in meters

Answers

299,792,458 is the right answer

22/22 is an even number greater than 20?

Answers

Answer:

yes

Explanation:

becuse it is an even  that is 2 number then 20

Answer:

Yes

Explanation:

It is because 22 is greater than 20

If a car with a mass of 4000 kg is accelerating at a rate of 2 ms and hits a tree what force does it have

Answers

That depends on the car's speed at the moment of impact, and how long it takes to stop after the impact.

It is NOT 8,000N. That answer would come from a totally incorrect application of " F = m a " . 8,000 Newtons is what it takes to accelerate that car in the first place, long before it hits the tree.

Force can be described as either a pull or a push

Now when a body with mass and acceleration hits an object, we say a collision has taken place, hence there will be transfer of energy within the system

Give data

mass = 4000kg

acceleration = 2m/s^2

We know that force is given as

Force = mass x acceleration

Substitute our given data into the expression for force

Force = 4000 x 2Force = 8000N

For more information on force kindly visit

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what are the applications of measurement?​

Answers

Things like thermometers, barometers, and water, gas, and electric meters, automotive speedometer and fuel gage, and compasses.

metal sphere having an excess of +5 elementary charges has a net electric charge of

Answers

Answer:

[tex]q=+8.01\cdot 10^{-19}\ coulombs[/tex]

Explanation:

Elementary charge

The elementary charge, denoted by the symbol e is the electric charge carried by a proton or, equivalently, the magnitude of a negative electric charge carried by an electron, which has charge −e.

The value of the elementary charge is a fundamental constant in physics:

[tex]\mathbf{e}=1.60217662 \cdot 10^{-19}\ coulombs[/tex]

If a metal sphere has an excess of +5 elementary charge, then it has a net charge of:

[tex]q=5*\mathbf{e}=+5*1.60217662 \cdot 10^{-19}\ coulombs[/tex]

[tex]\boxed{q=+8.01\cdot 10^{-19}\ coulombs}[/tex]

Assignment 1. Define Couple?

Answers

two individuals of the same sort considered together

calculate the monentun pf 75 kg bicycle and boy who has ghe velocitg of 3m/s

Answers

Explanation:

n=75 kg

v=3m/s

m=n×v

m=75x3

m= 225n

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