You want to double the radius of a rotating solid sphere while keeping its kinetic energy constant. (The mass does not change.) To do this, the final angular velocity of the sphere must be Group of answer choices

Answer:

true

Explanation:

Answer:

Dang bro what school you in?

Answer:

The value of the average convection coefficient is 20 W/Km².

Explanation:

Given that,

For first object,

Characteristic length = 0.5 m

Surface temperature = 400 K

Atmospheric temperature = 300 K

Velocity = 25 m/s

Air velocity = 5 m/s

Characteristic length of second object = 2.5 m

We have same shape and density of both objects so the reynold number will be same,

We need to calculate the value of the average convection coefficient

Using formula of  reynold number for both objects

[tex]R_{1}=R_{2}[/tex]

[tex]\dfrac{u_{1}L_{1}}{\eta_{1}}=\dfrac{u_{2}L_{2}}{\eta_{2}}[/tex]

[tex]\dfrac{h_{1}L_{1}}{k_{1}}=\dfrac{h_{2}L_{2}}{k_{2}}[/tex]

Here, [tex]k_{1}=k_{2}[/tex]

[tex]h_{2}=h_{1}\times\dfrac{L_{1}}{L_{2}}[/tex]

[tex]h_{2}=\dfrac{q}{T_{2}-T_{1}}\times\dfrac{L_{1}}{L_{2}}[/tex]

Put the value into the formula

[tex]h_{2}=\dfrac{10000}{400-300}\times\dfrac{0.5}{2.5}[/tex]

[tex]h_{2}=20\ W/Km^2[/tex]

Hence, The value of the average convection coefficient is 20 W/Km².

Explanation:

Acceleration is the change in velocity over time.

a = Δv / Δt

a = (26 m/s − 9 m/s) / 8 s

a ≈ 2.1 m/s²

Answer:

2m/s

Explanation:

The formula for acceleration can be found by [ a = f/m ]

We are given the force [ 100N ] and the mass [ 50g ].

We can use these values to solve for the acceleration.

a = 100/50

a = 2m/s

Best of Luck!

Answer:

[tex]a=6.4\ m/s^2[/tex]

Explanation:

Given that,

Initial velocity, u = 0

It falls from a height of 3 m and it takes 968 ms to reach the ground.

We need to find the acceleration due to gravity on Gazorpzorp. Using second equation of motion to find a. It can be given by :

[tex]s=ut+\dfrac{1}{2}at^2[/tex]

u = 0 (at rest) and a = g

[tex]s=\dfrac{1}{2}at^2\\\\a=\dfrac{2s}{t^2}\\\\a=\dfrac{2(3)}{(968\times 10^{-3})^2}\\\\a=6.4\ m/s^2[/tex]

So, the acceleration due to gravity on Gazorpzorp [tex]6.4\ m/s^2[/tex].

Answer:

W = 0J

Explanation:

The work done by the dresser is described as

W = f d (cos θ)

F has been given as the weight of this dresser. And it is 3500 N

d = 0 m

When you put these values into the equation

W = 3500 x 0 x cosθ

W = 0 J

This value tells us that the work done on this dresser is zero. No work has been done. Therefore the last option answers the question.

Answer: C is correct

Explanation:

Answer:

The cart starts out in position A with high potential energy, low kinetic energy, and some thermal energy. As the cart progresses into position B, the kinetic energy begins to increase and the potential energy begins to decrease; as the thermal energy increases as thermal energy from the track is transferred to the cart through friction. Once the cart reaches position C, it has high kinetic energy, low potential energy, and some thermal energy. At position D, the cart has high potential energy, low kinetic energy, and some thermal energy. The potential energy throughout is correlated to gravity, the kinetic energy is correlated to momentum, and the thermal energy is correlated to friction. The potential energy is at its maximum during position A, and its minimum at position C; the kinetic energy is at its maximum during position C, and its minimum at position A; the thermal energy is at its maximum during position B, and its minimum at position A.

Explanation:

Answer:

Cart A starts out on the top of the hill, it has great potential energy, low kinetic energy, and some thermal energy. Cart B is going down the hill which increased the kinetic energy and the thermal energy while the potential energy is decreasing. Cart C is at the bottom of the hill, having high kinetic energy, low potential energy and some thermal energy. Cart D is at the top of a smaller hill, giving it high potential energy, low kinetic energy and little thermal energy.

These changes occur because when an object is at a high place, it will have high potential energy, and low kinetic energy, and as the height goes down, the kinetic energy increases and the potential energy will decrease.  

Explanation:

here's my version of answer

Answer:

a) W=2.425kJ

b) [tex]\Delta E=2.425kJ[/tex]

c) [tex]T_f=20.06^{o}C[/tex]

d) Q=-2.425kJ

Explanation:

a)

First of all, we need to do a drawing of what the system looks like, this will help us visualize the problem better and take the best possible approach. (see attached picture)

The problem states that this will be an ideal system. This is, there will be no friction loss and all the work done by the object is transferred to the water. Therefore, we need to calculate the work done by the object when falling those 10m. Work done is calculated by using the following formula:

[tex]W=Fd[/tex]

Where:

W=work done [J]

F= force applied [N]

d= distance [m]

In this case since it will be a vertical movement, the force is calculated like this:

F=mg

and the distance will be the height

d=h

so the formula gets the following shape:

[tex]W=mgh[/tex]

so now e can substitute:

[tex]W=(25kg)(9.7 m/s^{2})(10m)[/tex]

which yields:

W=2.425kJ

b) Since all the work is tansferred to the water, then the increase in internal energy will be the same as the work done by the object, so:

[tex]\Delta E=2.425kJ[/tex]

c) In order to find the final temperature of the water after all the energy has been transferred we can make use of the following formula:

[tex]\Delta Q=mC_{p}(T_{f}-T_{0})[/tex]

Where:

Q= heat transferred

m=mass

[tex]C_{p}[/tex]=specific heat

[tex]T_{f}[/tex]= Final temperature.

[tex]T_{0}[/tex]= initial temperature.

So we can solve the forula for the final temperature so we get:

[tex]T_{f}=\frac{\Delta Q}{mC_{p}}+T_{0}[/tex]

So now we can substitute the data we know:

[tex]T_{f}=\frac{2 425J}{(10000g)(4.1813\frac{J}{g-C})}+20^{o}C[/tex]

Which yields:

[tex]T_{f}=20.06^{o}C[/tex]

d)

For part d, we know that the amount of heat to be removed for the water to reach its original temperature is the same amount of energy you inputed with the difference that since the energy is being removed this means that it will be negative.

[tex]\Delta Q=-2.425kJ[/tex]

Explanation:

the acceleration will be unchanged according to newton second law of motion

A locomotive engine pulls a train with a constant force then its acceleration will increase if more coaches are added to the train because the mass of the system would increase

Newton's Second Law states that The resultant force acting on an object is proportional to the rate of change of momentum.

Force = mass ×acceleration

As given in the problem if a locomotive engine pulls a train with a constant force

As given the force is constant but if the number of coaches increases the mass of the train increase to balance the constant force acceleration will decrease.

Thus, if a locomotive engine pulls a train with a constant force then its acceleration will increase if more coaches are added to the train because the mass of the system would increase.

Learn more about Newton's second law, here refer from the link,

brainly.com/question/13447525

#SPJ2

Answer:

Gravitational

Electrostatic

magnetic

Frictional

gravitational

electrostatic

magnetic

frictional

hope it helps

pls mark as brainliest

Answer:

Number one is C.Both

Number two is A. throw upwards

Number three is B. react his grapple... shooting upward

Answer:

v = 6.89 [m/s]

velocity = 0

Explanation:

To solve this problem we must use the definition of speed which is defined by the following expression of physics, such as the relationship between distance and time.

v = x/t

where:

v = speed [m/s]

x = distance = 400 [m]

t = time = 58 [s]

v = 400/58

v = 6.89 [m/s]

The velocity is a vector, since the racing car moves in circles IE its movement started where it ended, its velocity is zero.

Explanation:

Chimpanzees are genetically closest to humans, and in fact, chimpanzees share about 98.6% of our DNA. We share more of our DNA with chimpanzees than with monkeys or other groups, or even with other great apes! We also both play, have complex emotions and intelligence, and a very similar physical makeup.

(I hope that's good) :)

Answer:

That is Melon Collision and the second blank is Lone Collision.

Explanation:

Answer: STOP LOOKING FOR ANSWERS OMG:(((((9

Explanation:

Answer:

30.81°

Explanation:

Angle of refraction= sin⁻¹ 0.5122 = 30.81°.

Hope this helped!

PLEASE MARK ME AS BRAINLIEST!

Answer:

nice app is brainly heheh........

Answer:

The acceleration is 100m

Explanation:

Answer:

1.) Everything that moves, will eventually come to a stop. Rest is the “natural” state of all objects

Of all physics misconceptions, this is the most common. Even the great philosopher Aristotle, included it into his most important contribution to the field, his famous Laws of Motion. But now we know it is wrong because Newton’s First Law of Motion tells us that “everything at rest will stay at rest, and everything in motion will stay in motion, unless acted upon by an external force.”

The first statement seems reasonable enough, but the second part is a little bit murky. The reason this confusion persists boils down to the fact that we are unable to identify the force that stops all motion, which is friction. Friction is a force that acts between two objects that are in contact and are moving relative to each other. When we roll a ball, it stops because of the frictional force acting between it and the floor.

2.) A continuous force is needed for continuous motion

This misconception is a direct consequence of the first one. While this is true, if you are, for example, pushing a grocery cart in a supermarket, again this is only because there is friction involved. The force you apply to keep an object moving is only to counteract the frictional force. If you were to throw a rock on outer space, it would travel with a constant velocity forever, unless it hits something, of course. This is because space is mostly empty (it has trace elements of gas and dust throughout), and there would not be any frictional force acting on that rock.

3.) An object is hard to push because it is heavy

This is one of the most common misconceptions because it’s something we see and feel everyday. While a heavy object is really hard to push, it is not because of its weight, but because of its inertia or mass. Inertia is an objects resistance to change in motion. It is important to note that inertia is resistance to “change motion” rather than just motion itself. When, I was a kid, I imagined that it would be easy to carry and push massive objects when in outer space, but not surprisingly, my younger self was wrong.,

With that said… Since these objects still have mass despite being weightless, this mass represents the object’s inertia.

4.) Planets revolve around the sun because they are pushed by gravity

We have to remember that gravity — the weakest of the four fundamental forces — is an attractive force. The reason why planets revolve around the Sun can be chalked up to the fact that the planets were already spinning within the protoplanetary disk encircling a young Sun. Gravity merely keeps the planets in orbit around the Sun, but it isn’t necessarily the one thing pushing the planets along their orbital plane.

5.)  Heavier objects fall faster than lighter ones

This misconception is already debunked long ago by Galileo on his experiment when he dropped two objects with different masses on the Leaning Tower of Pisa. He has shown on that experiment that objects move downward with the same acceleration.

Again, the problem comes from not being able to identify another force that is involved, which is air resistance. All objects moving through air, and hence, all falling objects, experience air resistance. This force is proportional to the area of the object in the direction of motion. Usually, this force is negligible, but for light objects — with weight comparable to the air resistance, like a feather — it will have a big effect. This is ultimately confirmed by the famous hammer and feather drop experiment on the moon.

6.) There is no gravity in outer space

There is gravity in outer space, it is just weaker than what we experience here on Earth. Astronauts that are orbiting the Earth don’t experience gravity because they are free-falling (yes, you read that right). All satellites, including the moon and the planets, are in a constant state of freefall.

They just also have a tangential velocity with their free fall, that is why they don’t crash to what they are orbiting. When something is in free fall, it becomes weightless. This is why Kate Upton can do a photo shoot in zero gravity here on Earth. The plane that they are riding in actually went into free fall to do that.

7.) Planets move in circular orbits around the Sun

Planets actually move in elliptical orbits around the sun (with the Sun being the focus of the ellipse). This is actually the first of Kepler’s Three Laws of Planetary Motion, which deals with precisely how planets orbit the Sun.

One misconception deals with our seasons. Some might wrongly come to the conclusion that Earth’s proximity to the Sun dictates the seasons (summer is when Earth is closest to the Sun and winter is when it’s farther away), but that’s not entirely true. In reality, our seasons are caused by the tilt of Earth’s axis.

Answer:

the equipotential lines or surface are perpendicular to the electric field

Explanation:

In this exercise you are asked to explain the relationship between the direction of the equipotential lines and the electric field.

Electric field lines go from a positive charge to a negative charge, the specific shape of these lines depends on the charge distribution, let's look at two specific cases:

* in the case of point charge the lines are radial

* In the case of electric plates, they are lines perpendicular to the plates.

Equipotential surfaces are related to the elective field by

            Ex = - dV / dx

            Ey = -dV / dy

            Ez = -dV / dz

             E = Exi ^ + Ey j ^ + Ezk ^

remember electric potential is a scalar and the electric field is a vector quantity, therefore the equipotential lines or surface are perpendicular to the electric field. Specifically for

* point charge the equipotential surfaces are concentric with the charge

* For electrical plates equipotential lines are parallel to the plates.

Answer:

3.8 x 10^-11N

Explanation:

Given

M=72 kg

R=95 m

G=6.67x10^-11

Equation

Fg= 6.67x10^-11((72kg*72)/(95)^2)

Plug into calculator and get

3.8127756 x 10^-11

Answer:

Direction from A to B divided by time(30s)

Explanation:

Answer:

The magnitude of vector B is 13.7

Explanation:

Given that,

Component of vector B is

[tex]x=7.1[/tex]

[tex]y=8.2[/tex]

[tex]z=8.4[/tex]

We need to calculate the magnitude of vector B

Using given data

[tex]B=\sqrt{x^2+y^2+z^2}[/tex]

Put the value into the formula

[tex]B=\sqrt{(7.1)^2+(8.2)^2+(8.4)^2}[/tex]

[tex]B=13.7[/tex]

Hence, The magnitude of vector B is 13.7

Answer:

The acceleration of the woman is 0.44 m/s²

Explanation:

Given;

mass of the woman, m₁ = 90 kg

mass of the boy, m₂ = 60 kg

The force applied by the boy, f₂ = 40 N

The net horizontal force on the woman = 40 N

Apply Newton's second law of motion to determine the acceleration of the woman;

f = ma

a = f / m

a = 40 / 90

a = 0.44 m/s²

Therefore, the acceleration of the woman is 0.44 m/s²

Let [tex]u[/tex] be the initial velocity of the soccer ball at an angle of inclination of [tex]\theta_0[/tex] with the positive x-axis.

Given that:

[tex]\theta_0=45^{\circ}[/tex]

The horizontal distance covered by the projectile=20 m

Time of flight, [tex]t_f=2[/tex] seconds

Acceleration due to gravity, [tex]g= 10 m/s^2[/tex] downward.

As "north" and "up" as the positive x ‑ and y ‑directions, respectively.

So, [tex]g= -10 m/s^2[/tex]

As the acceleration due to gravity is in the vertical direction, so the horizontal component of the initial velocity remains unchanged.

The x-component of the initial velocity, [tex]u_x=u\cos\theta_0[/tex].

The horizontal distance covered by the projectile [tex]= u_x\times t_f[/tex]

[tex]\Rightarrow u_x\times t_f=20[/tex]

[tex]\Rightarrow u_x\times 2=20[/tex]

[tex]\Rightarrow u_x=10[/tex] m/s

So, the horizontal component of the velocity is 10 m/s which is constant and the graph has been shown in the figure (i).

Now,  [tex]u\cos(45^{\circ})=10[/tex] [as [tex]u_x=u\cos\theta_0[/tex]]

[tex]\Rightarrow u=10\sqrt{2}[/tex] m/s.

The vertical component of the initial velocity,

[tex]u_y= u\sin\theta_0[/tex]

[tex]\Rightarrow u_y=10\sqrt{2}\sin(45^{\circ})[/tex]

[tex]\Rightarrow u_y=10[/tex] m/s

Let v be the vertical component of the velocity at any time instant t.

From the equation of motion,

[tex]v=u+at[/tex]

where u: initial velocity, v: final velocity, a: constant acceleration, and t: time taken to change the velocity from u to v.

In this case, we have [tex]u=u_y, a= -10 m/s^2[/tex].

So at any time instant, t.

[tex]v=u_y+(-10)t[/tex]

[tex]\Rightarrow v=10-10t[/tex]

The vertical component of the velocity, v, is the function of time and related as [tex]v=10-10t[/tex].

This is a linear equation.

At 2 second, the vertical component of the velocity

v=10-10x2=-10 m/s.

The graph has been shown in figure (ii).