4 Two friction disks A and B are to be brought into contact withoutslipping when the angular velocity of disk A is 240 rpm counterclockwise. Disk A starts from rest at time t = 0 and is given a constantangular acceleration with a magnitude α. Disk B starts from rest attime t = 2 s and is given a constant clockwise angular acceleration,also with a magnitude α. Determine (a) the required angular acceleration magnitude α, (b) the time at which the contact occurs

Answer:

a. Power = 1000 Watts or 1 Kilowatts.

b. Current = 4 Amperes.

Explanation:

Given the following data;

Energy consumed = 1.8MJ = 1.8 × 10^6 = 1800000 Joules

Voltage = 250V

Time = 30 minutes to seconds = 30 * 60 = 1800 seconds

To find the power rating;

Power = energy/time

Substituting into the equation, we have;

Power = 1800000/1800

Power = 1000 Watts or 1 Kilowatts.

b. To find the current taken from the supply;

Power = current * voltage

1000 = current * 250

Current = 1000/250

Current = 4 Amperes.

Answer:

25 m/s

Explanation:

200/8 = 25

Answer:

16.6 m

Explanation:

Let d be the distance the other person is ahead of you. Since the other person is walking at a speed, v = 1.17 m/s, after picking the wallet, the other person moves a distance , vt in time, t = 10.5 s, the total distance covered by you till catch up is D = d + vt.

Also, you moves with a speed of v' = 2.75 m/s in time t = 10.5 s as you pick up the wallet, you covers a distance d' = v't at catch up.

At catch up, D = d'

d + vt = v't

d = v't - vt

d = (v' - v)t

Substituting the values of the variables into d, we have

d = (2.75 m/s - 1.17 m/s)10.5 s

d = (1.58 m/s)10.5 s

d = 16.59 m

d ≅ 16.6 m

So, the other person was 16.6 m ahead of you when you started running.

Answer:

[tex]<-0.5, 1.5, -3.5>\ \text{m/s}[/tex]

Explanation:

[tex]u_1[/tex] = Velocity of one lump = [tex]3x+3y-3z[/tex]

[tex]u_2[/tex] = Velocity of the other lump = [tex]-4x+0y-4z[/tex]

m = Mass of each lump = [tex]30\ \text{g}[/tex]

The collision is perfectly inelastic as the lumps stick to each other so we have the relation

[tex]mu_1+mu_2=(m+m)v\\\Rightarrow m(u_1+u_2)=2mv\\\Rightarrow v=\dfrac{u_1+u_2}{2}\\\Rightarrow v=\dfrac{3x+3y-3z-4x+0y-4z}{2}\\\Rightarrow v=-0.5x+1.5y-3.5z=<-0.5, 1.5, -3.5>\ \text{m/s}[/tex]

The velocity of the stuck-together lump just after the collision is [tex]<-0.5, 1.5, -3.5>\ \text{m/s}[/tex].

Answer:

Explanation:

When two charges of equal magnitude and sign approach each other, they interact through Coulomb's law

          F = [tex]k \frac{q_ 1q_2}{z^2 }[/tex]k q1 q2 / r2

In you case the house are of equal magnitude and sign

          q1 = q2 = q

          F = k q2 / r2

Let's analyze this expression, the charge is repulsive on each charge, when they are on a collision course as they approach they feel an electric field opposite to their direction of movement, this field decreases its speed, the closer they get, the greater the repulsive force. , up to the point where this force is equal to or greater than the impulse, therefore the point where the velocity reaches zero, for this reason the particles do not actually touch

Answer:

True

Explanation:

Answer:

B

Explanation:

Motion is movement, the teacher's movement is motion

Consider the balloon and air inside the flask to be in a closed system. Using the First Law of Thermodynamics to explain what happened to the balloon as heat was added by the environment.

Balloon will burst, due to more heat and in another flask air gets heated.

"The first law of thermodynamics states that energy can neither be created nor destroyed, only altered in form. For any system, energy transfer is associated with mass crossing the control boundary, external work, or heat transfer across the boundary. These produce a change of stored energy within the control volume."

"Heat is the energy that is transferred from one body to another as the result of a difference in temperature. If two bodies at different temperatures are brought together, energy is transferred i.e, heat flows—from the hotter body to the colder."

Know more about heat here

https://brainly.com/question/1429452

#SPJ3

Well we know it has to be greater than 300,000 km/s since we can't see it.

We can't calculate it any closer than that using the given information.

Answer:

Work required to empty the tank by pumping all of the water to the top of the tank = 1674700 Kgm/s^2

Explanation:

Volume of Circular cone = V = (1/3)πr2h

where r is the radius in meters

and h is the height in meters

Substituting the given values in above equation, we get -

V = [tex]\frac{1}{3} * 3.14 * 4^2 * 10 = 167.47[/tex] cubic  meters.

The force required will be equal to the mass of water in the cone

[tex]= 167.47 * 1000[/tex]

= 167470 Kg

Weight = Mass * g

= 167470 * 10

= 1674700 Kgm/s^2

Answer:

A is the answer okkkkkkkkkkkkkkkk

Answer:

Explanation:

Yes , it is possible .

When a negative charge moves towards a positive charge , it is moving in the direction of increasing electrical potential . In the whole process , its electrical potential energy decreases and its kinetic energy increases .

Actually the potential energy of a negative charge near a positive charge is negative and it is inversely proportional to distance .

V = - Qq / R , When R decreases , the negative value of potential increases . That means potential energy decreases .

Answer:

Speed = 10.24 m/s.

Explanation:

Given the following data;

Distance = 100m

Time = 9.77

To find her speed;

Speed can be defined as distance covered per unit time. Speed is a scalar quantity and as such it has magnitude but no direction.

Mathematically, speed is given by the equation;

[tex]Speed = \frac{distance}{time}[/tex]

Substituting into the equation, we have;

[tex]Speed = \frac{100}{9.77}[/tex]

Speed = 10.24 meter per seconds.

Answer:

No answer

Explanation:

no explanation

Answer:

2.66×10⁻⁹ N.

Explanation:

From the question,

Applying newton's law of universal gravitation,

Fg = GMm/r²............................... Equation 1

Where Fg = gravitational force, G = universal constant, M = mass of the mercury, m = mass of the human, r = radius of Mercury

Given: M = 3.31023 kg, M = 70 kg, r = 2.4106

Constant: G = 6.67×10⁻¹¹ Nm²/kg²

Substitute these values into equation 1

Fg = 6.67×10⁻¹¹(70×3.31023)/(2.4106²)

Fg = 2.66×10⁻⁹ N.

Answer:

A) i) Dynamic error ≈ 3.1%

   ii) phase shift ≈ -12°

B) 79971.89 rad/s

Explanation:

Given data :

Damping ratio = 0.5

natural frequency = 18,000 Hz

a) Calculate the dynamic error and phase shift in accelerometer output at an impart vibration of 4500 Hz

i) Dynamic error

This can be calculated using magnitude ratio formula attached below is the solution

dynamic error ≈ 3.1%

ii)  phase shift

This phase shift can be calculated using frequency dependent phase shift formula

phase shift ≈ -12°

B) Determine resonance frequency

  Wr = 2[tex]\pi[/tex] ( 18000 [tex]\sqrt{0.5}[/tex] ) = 79971.89 rad/s

C) The maximum magnitude ratio that the system can achieve

Answer:

Explanation:

Suppose that the turbines of a coal-fired plant are driven by hot gases at a temperature of 886 K. the temperature of the exhaust area is only 305 K,  the efficiency of this heat engine

Answer:

Part A

Newton's second law of motion states that the force applied to an object is directly proportional to the rate of change of momentum that is produced

Mathematically, we have;

F = m·v - m·u/Δt

Where;

m = The mass of the object

v = The final velocity of the object

u = The initial velocity of the object

Δt = The duration of motion of the object during change in velocity

Therefore, given that the mass, 'M', of the truck is larger than the mass, 'm', of the minivan, where the time of change in velocity Δt, and the initial and final velocities of both automobiles are the same such as in a sudden stop, the garbage ruck will exert more force than the minivan, and therefore, the garbage truck has a greater initial momentum before the automobiles are brought to a stop

Part B;

According to Newton's first law of motion, we have;

The use of a seat belt (and airbag for front seated passengers) will prevent dashboard or windscreen for the front passengers or the front seat for the passengers in the back, from being the item that stops the continued forward motion of the passengers in the car, which can lead to injury

Part C; The Newton's law of motion that act on a body at the point of impact is Newton's third law of motion, which states that the action and reaction are equal and opposite

Therefore, the action of the garbage truck on the minivan upon impact is equal to the reaction of the minivan to the force the garbage truck exerts on the minivan

Explanation:

Answer:

The warm seas create a large humid air mass. The warm air rises and forms a low pressure cell, known as a tropical depression.

Explanation:

Hurricanes arise in the tropical latitudes (between 10 degrees and 25 degrees N) in summer and autumn when sea surface temperature are 28 degrees C (82 degrees F) or higher.

Answer:

air

Explanation:

Answer:

Explanation:

1 ) Let the initial horizontal velocity of car be v .

For vertical displacement

vertical displacement h = 21.3 - 2.3 = 19 m

Time taken to fall by 19 m be t

19 = 1/2 x 9.8 t² ( initial downward velocity is zero )

t = 1.97 s

This is also the time taken to cover horizontal displacement of 54 m which is width of river .

horizontal speed v = 54 / 1.97 m /s

v = 27.41 m /s

2 )

At the time of landing on other side , car will have both vertical and horizontal speed .

vertical speed

v = u + gt

= 0 + 9.8 x 1.97 = 19.31 m /s

horizontal speed will remain same as  the initial speed = 27.41 m /s

Resultant speed = √ ( 27.41² + 19.31² )

= √ ( 751.3 + 372.87)

= 33.52 m /s

Answer:

hello your question is incomplete attached below is the complete and the required circuit diagrams

answer :

Ai) This proves that when the current across the resistor is doubled the value of the voltage across the resistor doubles as well

B) It is better to take more measurements in the range 20mA < I < 40mA because of the amount of temperature reached by the bulb and the change in resistance is affected by the temperature

hence At 0 mA current, there won't be any noticeable change

Explanation:

Ai) The voltage across the resistor will double when you double the current through the resistor

Given that : V = I*R.  

lets assume : I = 2 amperes , R = 3 ohms

V = 2*3 = 6 v

secondly lets assume double the value of  (I)   i.e. I = 4 amperes

hence : V = 4*3 = 12 volts

This proves that when the current across the resistor is doubled the value of the voltage across the resistor doubles as well

Aii) Showing the two data points from simulation

I1                    V1            I2= 2I1         V2=2V1       V1/ I1 =V2/I2

0.9*10^3     9 * 10^3     1.8*10^3       18*10^3          10 ohms

1.6 * 10^3    16 * 10^3    3.2*10^3     32*10^3         10 ohms

B) It is better to take more measurements in the range 20mA < I < 40mA because of the amount of temperature reached by the bulb and the change in resistance is affected by the temperature

hence At 0 mA current, there won't be any noticeable change

Answer:

a)  i = 0.746 A, b)   # _electron = 2.44 10¹⁹ electrons,  c)   E = 1.87 10⁴ J

Explanation:

a) The definition of current is the charge per unit of time

           i = Q / t

           i = 1.56 / 2.09

           i = 0.746 A

b) Let's look for the cargo in passing at this time

           i = Q / t

           Q = i t

            Q = 0.746 5.24

            Q = 3.904 C

an electron has a charge e = -1.6 10⁻¹⁹ C, let's use a direct proportions rule

            # _electron = 3.904 C (1 electron / 1.6 10⁻¹⁹)

            # _electron = 2.44 10¹⁹ electrons

the number of electrons has to be an integer

c) In this part you are asked to calculate the power

            P = V i

            P = 12 0.746

            P = 8.952 W

            P = E/t

            E = P t

            E = 8.952 2.09

            E = 1.87 10⁴ J

Answer:

The frequency must be: [tex]725\,\,10^{12} \,Hz[/tex]

Explanation:

If the work function of the metal ([tex]\phi[/tex]) is 3 eV, then we can use the formula for the kinetic energy of an ejected electron:

[tex]KE= h*f-\phi[/tex]

considering for the minimum KE = 0, and using the Plank constant h in eV s as: 4.14 * 10 ^(-15) eV s, to solve for the frequency:

[tex]h*f=\phi\\4.14*10^{-15} * f = 3\\f=3*10^{15} /4.14\,\,\frac{1}{s} \\f=725\,10^{12} \,Hz[/tex]

Answer:

42,250

Explanation:

It goes inside=

Displacemt

It does work=

Work done

To find efficiency of jule we do=

Dicplacement × Work done

650 × 65

42,250

Please mark me as a brainlist

Answer:

The answer is "Choice C ".

Explanation:

The relationship between the E and V can be defined as follows:

[tex]\to E= -\Delta V[/tex]

Let,

[tex]\to E= \frac{\delta V}{\delta x}[/tex]

When E=0

[tex]\to \frac{\delta V}{\delta x}=0[/tex]

v is a constant value

Therefore, In the electric potential in a region is a constant value then the electric-field must be into zero that is everywhere in the given region, that's why in this question the "choice c" is correct.

Answer:

the height above the ground through Mr. Voytko lifted the apple is 2.5 m.

Explanation:

Given;

energy of Mr. Voytko, E = 7.35 J

mass of the apple, m = 0.3 kg

Apply the principle of conservation of energy.

Energy of Mr. Voytko = Potential energy of the apple due to its height above the ground.

E = mgh

where;

h is the height above the ground through Mr. Voytko lifted the apple.

g is acceleration due to gravity = 9.8 m/s²

h = E / (mg)

h = 7.35 / (0.3 x 9.8)

h = 2.5 m

Therefore, the height above the ground through Mr. Voytko lifted the apple is 2.5 m.