A circular disk of radius 2.0 m rotates, starting from rest, with a constant angular acceleration of 20.0 rad/s2. What is the tangential acceleration of a point on the edge of the disk at the instant that its angular speed is 1.0 rev/s?a. 40 m/s2.
b. 79 m/s2.
c. zero m/s2.
d. 120 m/s2.
e. 110 m/s2.

Answer:

C 1 degree

Explanation:

Answer:

The gravity is 87.4% as strong as at the Earth’s surface.

Explanation:

Hope this helped!

Answer:

The biggest reasons the U.S. hasn't adopted the metric system are simply time and money. When the Industrial Revolution began in the country, expensive manufacturing plants became a main source of American jobs and consumer products.

Explanation:

Answer:

f= 6 Hz

Explanation:

       [tex]T = \frac{500 msec}{3} = 166.7 msec (1)[/tex]

Answer:

I = 2.99 A

Explanation:

magnetic field, B = 0.96 T, length of wire, l = 2.7 m, mass of wire, m = 0.79 kg.

Since it is expected that the wire would vibrate or move in the magnetic field, from Newton's second law of motion;

F = mg

where F is the force on the wire, m is the mass of the wire and g is the acceleration due to gravity.

But,

F = BIL

⇒ BIL = mg

0.96 x I x 2.7 = 0.79 x 9.8

2.592I = 7.742

I = [tex]\frac{7.742}{2.592}[/tex]

 = 2.9869

I = 2.99 A

The required minimum current is 2.99 A.

Answer:

(1) 1000 N (2) 1 m/s²

Explanation:

(1) Given that,

The mass of a car, m = 1000 kg

Radius of a circular track, r = 100 m

Speed of the car, v = 10 m/s

We need to find the magnitude of the centripetal force acting on the car. The magnitude of the centripetal force is given by :

[tex]F=\dfrac{mv^2}{r}\\\\F=\dfrac{1000\times (10)^2}{100}\\\\F=1000\ N[/tex]

So, the correct option is (c) i.e. 1000 N

(2).The mass of a car, m = 1000 kg

Radius of a circular track, r = 100 m

Speed of the car, v = 10 m/s

We need to find the magnitude of the centripetal acceleration of the car. The magnitude of the centripetal acceleration is given by :

[tex]a=\dfrac{v^2}{r}\\\\a=\dfrac{(10)^2}{100}\\\\a=1\ m/s^2[/tex]

So, the correct option is (b) i.e. [tex]1\ m/s^2[/tex]

Answer:

1) The mass of the continent is approximately [tex]1.608\times 10^{21}[/tex] kilograms.

2) The kinetic energy of the continent is approximately [tex]8.04\times 10^{16}[/tex] joules.

3) The speed of the 77 kg-jogger would be approximately [tex]45.698\times 10^{6}[/tex] meters per second.

Explanation:

1) The mass of the North American continent can be estimated by using the following formula under the assumption that rock has an uniform density:

[tex]m = \rho \cdot L^{2}\cdot h[/tex] (1)

Where:

[tex]m[/tex] - Mass of the continent, measured in kilograms.

[tex]\rho[/tex] - Average density of the rock, measured in kilograms per cubic meter.

[tex]L[/tex] - Side of the continent, measured in meters.

[tex]h[/tex] - Depth of the continent, measured in meters.

If we know that [tex]\rho = 2620\,\frac{kg}{m^{3}}[/tex], [tex]L = 4.450\times 10^{6}\,m[/tex] and [tex]h = 31\times 10^{3}\,m[/tex], then the mass of the continent is:

[tex]m = \left(2620\,\frac{kg}{m^{3}} \right)\cdot (4.450\times 10^{6}\,m)^{2}\cdot (31\times 10^{3}\,m)[/tex]

[tex]m = 1.608\times 10^{21}\,kg[/tex]

The mass of the continent is approximately [tex]1.608\times 10^{21}[/tex] kilograms.

2) By assuming that continent can be represented as a particle, we define its kinetic energy as:

[tex]K = \frac{1}{2}\cdot m \cdot v^{2}[/tex] (2)

Where:

[tex]K[/tex] - Translational kinetic energy, measured in joules.

[tex]v[/tex] - Motion rate of the continent, measured in meters per second.

If we know that [tex]m = 1.608\times 10^{21}\,kg[/tex] and [tex]v = 1\times 10^{-2}\,\frac{m}{s}[/tex], then the kinetic energy of the continent is:

[tex]K = \frac{1}{2}\cdot (1.608\times 10^{21}\,kg)\cdot \left(1\times 10^{-2}\,\frac{m}{s} \right)^{2}[/tex]

[tex]K = 8.04\times 10^{16}\,J[/tex]

The kinetic energy of the continent is approximately [tex]8.04\times 10^{16}[/tex] joules.

3) The speed of the jogger is derived from the definition of translational kinetic energy:

[tex]v = \sqrt{\frac{2\cdot K}{m} }[/tex]

If we know that [tex]K = 8.04\times 10^{16}\,J[/tex] and [tex]m = 77\,kg[/tex], then the expected speed of the jogger is:

[tex]v = \sqrt{\frac{2\cdot (8.04\times 10^{16}\,J)}{77\,kg} }[/tex]

[tex]v\approx 45.698\times 10^{6}\,\frac{m}{s}[/tex]

The speed of the 77 kg-jogger would be approximately [tex]45.698\times 10^{6}[/tex] meters per second.

Answer:

A = 2.26 m

Explanation:

Given that,

The total mechanical energy of the block spring system is 512 J

Let the spring constant, k = 200 N/m

We need to find the amplitude for this oscillation. The mechanical energy of the spring mass system is given by :

[tex]E=\dfrac{1}{2}kA^2[/tex]

k is spring constant

[tex]A=\sqrt{\dfrac{2E}{k}} \\\\A=\sqrt{\dfrac{2\times 512}{200}} \\A=2.26\ m[/tex]

So, the amplitude of the oscillation is 2.26 m

Answer:

The kinetic energy remains same and gravitational potential energy increases.

Explanation:

KINETIC ENERGY:

As, we know that the kinetic energy depends upon the speed of the object. Hence, the kinetic energy is given as:

K.E = (1/2)mv²

where,

m = mass

v = speed

K.E = Kinetic Energy

Since, the friction is ignored, therefore the speed of roller coaster will remain same.

Therefore, its Kinetic Energy will also remain same.

POTENTIAL ENERGY:

The potetial energy od a body depends upon its height, as follows:

P.E = mgh

where,

P.E = potential Energy

m = mass

g = acceleration due to gravity

h = height

As, the roller coaster moves up hill its height increases.

Therefore, its potential energy will also increase.

hence, the correct option is:

The kinetic energy remains same and gravitational potential energy increases.

Answer:

(a) W₁ = 3293.06 J = 3.293 KJ

(b) W₂ = 0 J

(c) W₃ = - 506.625 J = - 0.506 KJ

(d) W₄ = 0 J

(e) W = 2786.435 J = 2.786 KJ

Explanation:

The complete question has following parts:

(a) First gas expands from a volume of 1 L to 6 L at a constant pressure of 6.5 atm

(b) Second, the gas is cooled at constant volume until the pressure falls to 1 atm

(c) Third, the gas is compressed at a constant pressure of 1 atm from a volume of 6 L to 1 L.

(d) Finally the gas is heated until its pressure from 1 atm to 6.5 atm at constant volume

(e) what is the net work?

ANSWERS:

(a)

The work done by a gas at constant pressure is given as follows:

W = PΔV

where,

W = Work done by the gas

P = Constant Pressure of the Gas

ΔV = Change in Volume of The gas

Therefore, for the first step:

P = P₁ = (6.5 atm)(1.01325 x 10⁵ Pa/1 atm) = 6.58613 x 10⁵ Pa

ΔV = ΔV₁ = 6 L - 1 L = (5 L)(0.001 m³/1 L) = 5 x 10⁻³ m³

W = W₁

Therefore,

W₁ = (6.58613 x 10⁵ Pa)(5 x 10⁻³ m³)

W₁ = 3293.06 J = 3.293 KJ

(b)

The work done at a constant volume by a gas is always zero due to no change in volume:

W₂ = P₂ΔV₂

W₂ = P₂(0)

W₂ = 0 J

(c)

For the third step:

P = P₃ = (1 atm) = 1.01325 x 10⁵ Pa

ΔV = ΔV₃ = 1 L - 6 L = (- 5 L)(0.001 m³/1 L) = - 5 x 10⁻³ m³

W = W₃

Therefore,

W₃ = (1.01325 x 10⁵ Pa)(-5 x 10⁻³ m³)

W₃ = - 506.625 J = - 0.506 KJ

(d)

The work done at a constant volume by a gas is always zero due to no change in volume:

W₄ = P₄ΔV₄

W₄ = P₄(0)

W₄ = 0 J

(e)

Hence, the net work is given as follows:

W = W₁ + W₂ + W₃ + W₄

W = 3293.06 J + 0 J + (- 506.625 J) + 0 J

W = 2786.435 J = 2.786 KJ

Answer:

Explained below

Explanation:

When one sits in a parked bus, and another bus is moving alongside, it means the other bus is moving relative to you. However, this makes the brain register in such a way that it's feels the bus you are in is the one moving.

In the second case where both buses are moving in opposite directions, the brain will register it in such a way that it seems the bus in which you are at is moving at a far higher speed than the speed in which it is actually moving.

This is because the relative velocity of the other vehicle is higher and it is therefore what makes your brain think your bus is moving at a faster speed.

Answer:

lol what

Explanation:

Answer:

25.82 m/s

Explanation:

We are given;

Force exerted by baseball player; F = 100 N

Distance covered by ball; d = 0.5 m

Mass of ball; m = 0.15 kg

Now, to get the velocity at which the ball leaves his hand, we will equate the work done to the kinetic energy.

We should note that work done is a measure of the energy exerted by the baseball player.

Thus;

F × d = ½mv²

100 × 0.5 = ½ × 0.15 × v²

v² = (2 × 100 × 0.5)/0.15

v² = 666.67

v = √666.67

v = 25.82 m/s

This question involves the concepts of the law of conservation of energy and kinetic energy.

The baseball leaves the hand with a velocity of "25.82 m/s".

From the law of conservation of energy the work done on the ball must be equal to the kinetic energy of the ball:

[tex]W=K.E\\\\Fd=\frac{1}{2}mv^2\\\\v=\sqrt{\frac{2Fd}{m}}\\\\v=\sqrt{\frac{2(100\ N)(0.5\ m)}{0.15\ kg}}[/tex]

where,

F = force applied = 100 N

d = displacement of ball = 0.5 m

m = mass of ball = 0.15 kg

v = 25.82 m/s

Learn more about the law of conservation of energy here:

brainly.com/question/20971995?referrer=searchResults

The attached picture explains the law of conservation of energy.

Answer:

[tex]\boxed {\boxed {\sf a\approx -0.08 \ m/s^2}}[/tex]

Explanation:

Acceleration can be found by dividing the change in velocity by the time.

[tex]a=\frac{v_f-v_i}{t}[/tex]

The final velocity is 3 meters per second. The initial velocity is 8 meters per second.

We need to convert the time to seconds.

So, we know that:

[tex]v_f=3 \ m/s \\v_i= 8 \ m/s\\t= 60 \ s[/tex]

Substitute the values into the formula.

[tex]a=\frac{3 \ m/s - 8 \ m/s}{60 \ s}[/tex]

Solve the numerator.

[tex]a=\frac{-5 \ m/s}{60 \ s}[/tex]

Divide.

[tex]a=-0.0833333333 \ m/s/s[/tex]

Let's round to the nearest hundredth.

The 3 in the thousandth place tells us to leave the 8 in the hundredth place.

[tex]a\approx -0.08 \ m/s^2[/tex]

The cyclist's acceleration is about [tex]\boxed {-0.08 m/s^2}[/tex]

Answer:

Arsenic (As)

Explanation:

Arsenic is the only answer choice that has five valence electrons like the electron dot structure shows.

Answer:

Arsenic (As)

Explanation:

Answer:

electrical to mechanical

Explanation:

Answer: See the explanation.

Explanation:

When we say a substance is magnetic it means the atoms are lined in a way that created a magnetic field that goes from one side to the other

These are essentially two aspects of the same thing, because a changing electric field creates a magnetic field, and a changing magnetic field creates an electric field. This is the relationship.

Answer: Copper isn't ferromagnetic,

Aluminum isn't ferromagnetic,

String does have a ferromagnetic property

Answer:

y = 6 10⁻² m

Explanation:

This is a diffraction exercise which is described by the expression

          a sin θ = m λ

we can use trigonometry to find the distance from the inside of the screen to the dark point (y)

          tan θ = y / L

angles are very small in diffraction experiments, so we can approximate

          tan θ = sin θ /cos θ = sin θ

          sin θ = y / L

substituting

         a (y / L) = m λ

Let's find the points where the intensity becomes zero

         y = m L λ / a

λ₁ = 4.0 10⁻⁷ m

m = 1

          y = 1 2.0 4.0 10⁻⁷/ 4.0 10⁻⁵

          y = 2 10⁻² m

m = 2

          y = 4 10⁻² m

λ₂ = 6.0 10⁻⁷ m

m = 1

          y = 1 2.0 6.0 10⁻⁷ / 4.0 10⁻⁵

          y = 3 10⁻² m

m = 2

          y = 6 10⁻² m

if we want a point where the two colors are dark, we set the two expressions equal

          y₁ = y₂

          m₁ L  λ₁ / a = m₂ L  λ₂ / a

          m₁/m₂ =  λ₂/λ₁

          m₁ / m₂ = 6 10⁻⁷ / 4 10⁻⁷

          m₁ / m₂ = 1.5

since the quantities m must be integers, the smallest relation that the relation fulfills is

            m₁ = 3

            m₂ = 2

the distance for this destructive interference is

           y = 3 2 4.0 10⁻⁷ / 4.0 10⁻⁵

           y = 6 10⁻² m

this is the first point where the minimum of the two wavelengths coincide

Answer:

The position of the object at [tex]t = 5\,s[/tex] is 130.167 meters.

Explanation:

Let [tex]a(t) = 5\cdot t\,\left[\frac{m}{s^{2}} \right][/tex] the acceleration experimented by the object along the x-axis. We obtain the equation for the position of the object by integrating in acceleration formula twice:

Velocity

[tex]v(t) = \int {a(t)} \, dt[/tex] (1)

[tex]v(t) = 5\int {t} \, dt[/tex]

[tex]v(t) = \frac{5}{2}\cdot t^{2}+v_{o}[/tex] (2)

Where [tex]v_{o}[/tex] is the initial velocity of the object, measured in meters per second.

Position

[tex]s(t) = \int {v(t)} \, dt[/tex] (3)

[tex]s(t) = \frac{5}{2}\int {t^{2}} \, dt+v_{o}\int \, dt[/tex]

[tex]s(t) = \frac{5}{6}\cdot t^{3}+v_{o}\cdot t + s_{o}[/tex] (4)

Where [tex]s_{o}[/tex] is the initial position of the object, measured in meters per second.

If we know that [tex]s_{o} = 6\,m[/tex], [tex]v_{o} = 4\,\frac{m}{s}[/tex] and [tex]t = 5\,s[/tex], then the position of the object is:

[tex]s(5) = \frac{5}{6}\cdot (5)^{3}+\left(4\right)\cdot (5)+6[/tex]

[tex]s(5) = 130.167\,m[/tex]

The position of the object at [tex]t = 5\,s[/tex] is 130.167 meters.

Answer:

Image result for total velocity definition

The average speed of an object is defined as the distance traveled divided by the time elapsed.

Explanation:

Answer:

Answer is (b) Mercury, venus and Mars.

Explanation:

i think b is correct!!

;-) :-) :-) :-)

Answer:

Natural gas is non renewable energy.

Explanation:

Because they were formed from the buried reamains of plants and animals that live a million years ago. It is formed from fossil fuels.

Answer:

[tex]0.00005202\ \text{rad}=0.003^{\circ}[/tex]

Explanation:

d = Diameter of typical neutron star = 20 km = 20000 m

D = Distance between Earth and Moon = [tex]384.4\times 10^6\ \text{m}[/tex]

Here, [tex]D>>d[/tex] so we use small angle approximation

[tex]\delta=\dfrac{d}{D}\\\Rightarrow \delta=\dfrac{20000}{384.4\times 10^6}\\\Rightarrow \delta=0.00005202\ \text{rad}=\dfrac{0.00005202\times 180}{\pi}=0.003^{\circ}[/tex]

The angular diameter of the neutron star would be [tex]0.00005202\ \text{rad}=0.003^{\circ}[/tex] from Earth.

Answer:

Explanation:

Given

Maximum height H = 300m

Range (horizontal distance) = 380m

Required

Initial speed U and the angle of the ball when it was launched.​

Range = U√2H/g

380 = U√2(300)/9.8

380 = U√600/9.8

380 = 7.8246U

U = 380/7.8246

U = 48.57m/s

The initial speed is 48.57m/s

b) Using the formula for calculating time of flight;

T = 2Usin theta/g

9 = 2(48.57)sin theta/9.8

9*9.8 = 97.14sin theta

88.2 = 97.14sin theta

88.2/97.14 = sin theta

sin theta = 0.9079

theta = sin^-1(0.9079)

theta = 65.23°

hence the angle when the ball was launched is 65.23°

Answer:

 ρ = 19215 kg / m³ , the answer the correct  is D

Explanation:

All materials are sold when heated, in first approximation

              ΔV = β V₀ (T -T₀)

for this case

              ΔV = 4.20 10⁻⁶ Vo (1050 - 0)

              ΔV = 4.41 10⁻³ Vo m³

              V-Vo = 4.41 10⁻³ Vo

              V = 1.00441 Vo

density is defined by

           ρ = m / V

a T = 0ºc

            ρ₀ = m / Vo

aT= 1050ºC

           ρ = m / V

           ρ = m / (1,00441 Vo)

           ρ = 1 / 1.00441      m/Vo

          ρ = 0.9956 ρ₀

          ρ = 0.9956 19300

          ρ = 19215 kg / m³

when checking the answers the correct one is D

Answer:

b. matter

Explanation:

Waves disturb matter but do not transmit it.

Waves are disturbances that transmit energy from one point to another. Although they cause disturbances, they do not transfer the matters in the medium.

Answer: 1.14 kg*m/s

Explanation:

The first person explained everything right, they just forgot to convert the angular acceleration to rads/sec^2 from revs/sec^2. Once that is converted, your answer should come out right.

Another small thing, the answer there has an extra unnecessary step. It tells you to find the square root of w^2 to find w but that is unnecessary since the final equation asked for w^2. Hope this helps! :)

The moment of inertia I of the flywheel about its rotation axis is

Given

Angular displacement,

[tex]\theta = 30rev \\\\\theta = (30) * 2\pi rad \\\\\theta = 188.495rad[/tex]

Therefore, Final angular velocity (w) will be:

[tex]w^2 = 2\alpha\theta\\\\w^2 = 2 * (0.200 * 2\pi) * (188.49)\\\\w^2 = 473.73\\\\w = 21.76 rad/s[/tex]

Therefore,

moment of inertia

[tex]I = 2 * K / w^2[/tex]

[tex]I = 2 * 330 / 473.73[/tex]

[tex]I = 1.39kgm^2[/tex]

For more information on moment of inertia

https://brainly.com/question/19557854?referrer=searchResults

Answer:

Yeah it's ok I think. Also, I can't see the answer you gave so maybe updating the question would be nice.

Answer:

Make sure you look at the wording!

Explanation:

if the last word is increased, the answer is increased

if the last word is decreased, the answer is it decreases!