Read the following selections from the section "Mickey Guyton's Star-Spangled Banner."

A solid cylinder of mass 12.0 kgkg and radius 0.250 mm is free to rotate without friction around its central axis. If you do 75.

dybincka [34]

Answer:

The final angular velocity is 20rad/s

Explanation:

We are given;

mass, m = 12 kg

radius, r = 0.25 m

Work done;W = 75 J

Moment of inertia of cylinder, I = (1/2) mr²

Thus,

I = (1/2) x 12 x 0.25² = 0.375 kg.m²

Now, from work energy theorem,

Work done = Change in kinetic energy

So, W = KE_f - KE_i

Now, Initial Kinetic Energy (KE_i) = 0

Final Kinetic Energy; KE_f = (1/2)Iω²

So, KE_f = (1/2) x 0.375 x ω²

KE_f = 0.1875 ω²

Now, W = 75 J

Thus,

From, W = KE_f - KE_i, we have;

75 = 0.1875 ω² - 0

75 = 0.1875 ω²

ω² = 75/0.1875

ω² = 400

ω = √400

ω = 20 rad/s

5 0

3 years ago

A nerve signal travels 150 meters per second. Determine the number of kilometers that the nerve signal will travel in the same t

joja [24]

Explanation:

It is given that,

A nerve signal travels 150 meters per second. It is the speed of the nerve signal. We need to convert the number of kilometers that the nerve signal will travel in the same time.

We know that,

1 kilometer = 1000 meter

1 hour = 3600 seconds

$150\ \dfrac{m}{s}=150\times \dfrac{1/1000\ km}{1/3600\ h}$

$150\ m/s=540\ km/h$

So, the nerve signal will travel at the rate of 540 km/h. Hence, this is the required solution.

6 0

3 years ago

A ball of mass is released from rest at a height of 30 how fast is it going when it hits the ground

elena55 [62]

Answer:

If the height is in metres, the speed is 24.25m/s

7 0

3 years ago

Two balloons (m = 0.021 kg) are separated by a distance of d = 16 m. They are released from rest and observed to have an instant

evablogger [386]

(a) $2.56\cdot 10^{-5} C$

According to Newton's second law, the force experienced by each balloon is given by:

F = ma

where

m = 0.021 kg is the mass

a = 1.1 m/s^2 is the acceleration

Substituting, we found:

$F=(0.021)(1.1)=0.0231 N$

The electrostatic force between the two balloons can be also written as

$F=k\frac{Q^2}{r^2}$

where

k is the Coulomb's constant

Q is the charge on each balloon

r = 16 m is their separation

Since we know the value of F, we can find Q, the magnitude of the charge on each balloon:

$Q=\sqrt{\frac{Fr^2}{k}}=\sqrt{\frac{(0.0231)(16)^2}{9\cdot 10^9}}=2.56\cdot 10^{-5} C$

(b) $1.6\cdot 10^{14}$ electrons

The magnitude of the charge of one electron is

$e=1.6\cdot 10^{-19}C$

While the magnitude of the charge on one balloon is

$Q=2.56\cdot 10^{-5} C$

This charge can be written as

$Q=Ne$

where N is the number of electrons that are responsible for this charge. Solving for N, we find:

$N=\frac{Q}{e}=\frac{2.56\cdot 10^{-5}}{1.6\cdot 10^{-19}}=1.6\cdot 10^{14}$

5 0

3 years ago

What is the specific enthalpy of benzene vapor at 45 c and 0.7 atm absolute pressure, relative to a reference state of benzene v

vazorg [7]

The specific enthalpy of benzene vapor at 45 c and 0.7 atm absolute pressure, relative to a reference state of benzene vapor at 45 c and 1.27 atm absolute pressure will be 0 kJ/mol.

<h3>What is specific enthalpy and how was it calculated in the question?</h3>

A thermodynamic system has a property called enthalpy (H). It is calculated by the sum of the internal energy (U) of the thermodynamic system and the product of its volume (V) and pressure (p). The SI Unit is Joule (J).

Equation:

H = U+pV

The specific enthalpy of vapor can be defined as the amount of energy spent in order to transform a liquid substance into its vapor or gaseous form. The SI Unit is kJ/mol.

In the above question, the formula to be used is

P1/P2 = (Δ Hvap)/R)(1/T2-1/T1)

T1 & P1 --> the starting temperature & pressure respectively (= 1.27 atm and 45c),

T2 & P2 --> the final temperature & pressure respectively (= 0.7 atm and 45c),

R --> the real gas constant i.e. 8.314kJ/mol and

ΔHvap --> The specific enthalpy of vaporization.

Putting the values in the equation;

1.27/0.7=(ΔHvap/8.314)(1/45-1/45)

Hence as after subtracting the equation becomes 0, our final answer also comes out to be ΔHvap= 0 kJ/mol.

To know more about specific enthalpy, visit:

brainly.com/question/16244647

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6 0

2 years ago