a sharp image is formed when light reflects from a

Answer:

a. 3.81

Explanation:

F = GMm/r^2

F = (6.67 x 10^-11 x 28 x 1) / 7^2

F = 3.81 x 10^-11 N

1. false

2. true

I hope this helps ^-^

Explanation:

To find the volume of a box of Tissue (also known as a rectangular prism) just multiply the area of the base (length times width) by the height. The formula is V = l• w• h.

Answer:

It's plastic.

trust me it's plastic, i've rad it somewhere.

All of them have something that's not like the others.

-- Rubber is the only one on the list that has two repeated letters.

-- Plastic is the only one on the list thagt has no repeated letters.

-- Plastic is the only one on the list that has no 'r' in its name.

-- Copper is the only one on the list that is an element, not a compound.

-- Copper is the only good electrical conductor on the list.

-- Plastic is the only one on the list with more than six letters in its name.

-- Rubber is the only one on the list with no 'p' in its name.

-- Plastic is the only one on the list that doesn't end in "-er".

Answer :

Last choice

Answer:

its frequency is too low

Answer:

Explanation:

Angular momentum = [tex]I*w[/tex]

I = Moment of inertia

w = Angular velocity

Hollow pipe can be considered as hollow cylinder

Moment of Inertia of Hollow cylinder = [tex]Mr^2[/tex]

Moment of Inertia of solid cylinder= [tex]\frac{Mr^2}{2}[/tex]

Clearly Moment of inertia of hollow pipe is greater which states that Angular momentum of it will be greater.

For more information on this visit

https://brainly.com/question/23379286

Answer:

1.61 N/kg

Explanation:

Take the universal gravitational constant G as 6.67 × 10^(-11) Nm²/kg²

The required gravitational field strength

= 6.67 × 10^(-11) × 7.3 × 10^(22) / (1738000)²

= 1.61194103 N/kg

= 1.61 N/kg (corr. to 3 sig. fig.)

Answer:

c

Explanation:

Answer:

When objects fall to the ground, gravity causes them to accelerate. Acceleration is a change in velocity, and velocity, in turn, is a measure of the speed and direction of motion. Gravity causes an object to fall toward the ground at a faster and faster velocity the longer the object falls.

Explanation:

Answer:

T = 34/3 N

Explanation:

Magnitude of the friction force on 2kg block = 0.3x10x2 = 6N

Magnitude of the friction force on 4kg block = 0.2x10x4 = 8N

Magnitude of the acceleration of the blocks

F = ma

30 - 8 - 6 = (2+4)a

a = 8/3 m s^-2

Tension in the string connecting the two blocks

Consider the 2kg block,

T - f = ma

T - 6 = 2(8/3)

T = 34/3 N

Answer:

The magnification of an image is equal to the ratio of the image height to the object height.

Answer:

the intensity of the light after passing through the two polarizing filters is 4.11 units  

Explanation:

Given the data in the question;

the intensity of an unpolarized light; I₀ = 25.0 units

when the unpolarized light passes through the first polarizer, its intensity reduces to half of its initial value;

⇒ I₁ = I₀/2 = 25/2 = 12.5 units

the angle between the transmission axes of two polarizers is;

∅ = 55° - 0° = 55°

The intensity of the light after passing through two polarizing filters will be;

I₂ = I₁cos²∅      

we substitute

I₂ = 12.5 × cos²(55)

I₂ = 12.5 × 0.3289899

I₂ = 4.11 units

Therefore, the intensity of the light after passing through the two polarizing filters is 4.11 units

Answer:

x = 0.056 m

ΔKE = 0.489 J

Explanation:

Given that

Angle, θ = 38°

Length, L = 1.7 m

Mass, m = 0.09 kg

Spring constant, K = 590 N/m

If we use the Work-Energy theorem, then we know that Potential Energy, PE = Kinetic Energy, KE

This is mathematically written as

1/2kx² = mgH

The height, H we can get by using the relation

H = L.Sinθ

H = 1.7 * Sin 38

H = 1.7 * 0.6157

H = 1.047 m

Next, we use the Work-Energy theorem

1/2kx² = mgH

1/2 * 590 * x² = 0.09 * 9.8 * 1.047

295 * x² = 0.9234

x² = 0.9235 / 295

x² = 0.00313

x = √0.00313

x = 0.056 m

If the spring loses contact at x = 0.056, definitely, it will also lose contact at x = 0.8

Then we use the formula

ΔKE = mg(H - H1)

ΔKE = mg(xsinθ - x2.sinθ)

Where, x = 1.7 , x2 = 0.8

ΔKE = 0.09 * 9.8 (1.7 * sin 38 - 0.8 * sin 38)

ΔKE = 0.882(1.047 - 0.493)

ΔKE = 0.882 * 0.554

ΔKE = 0.489 J

Answer:

 r = 0.5297 m

Explanation:

In this exercise we use Newton's second law where the force is magnetic

         F = ma

centripetal acceleration

          a = v² / r

          F = q v x B = q v B sin θ

where the angle between the velocity and the magnetic field is 90º, therefore the sin 90 = 1

we substitute

          q v B= m v² / r

          r = [tex]\frac{m v^2 }{qv B}[/tex]

the mass of each isotope is

12C

          m12 = 6 m_proton + 6 m_neutrons

          m12 = (6 1,673 +6 1,675) 10⁻²⁷

          m12 = 20.088 10-27 kg

14C

          m14 = 6 m_proton + 8 m_neutron

          m14 = (6 1,673 + 8 1,675) 10-27

          m14 = 23,438 10⁻²⁷ kg

in the exercise they indicate that the velocity of the two particles is the same, therefore with the initial data we can calculate the parameters that do not change in the experiment.

           [tex]\frac{v}{qB} = \frac{r}{m_{12}}[/tex]

           v / qB = 0.454 / 20.088 10⁻²⁷

           v / qb = 2.26 10²⁵

this quantity remains constant, let's use the other data to calculate the radius

          r = 23.438 10⁻²⁷   2.26 10²⁵

         r = 5.297 10⁻¹ m

         r = 0.5297 m

Answer:

Just gonna take this at free points and yes you are right but I am confused on what you wanted us to do

Answer:

see that the correct one is B

Explanation:

To solve this exercise let us use the kinematic relations

           v² = v₀² - 2 a x

as they indicate that the car stops, therefore the final speed is yield v = 0

          x = v₀² / 2a

let's calculate

          x = 2²/(2 0.8)

         x = 2.5 m / s²

When reviewing the answers we see that the correct one is B

Answer:

3 m/s

Explanation:

A= F/m

12,000/ 4000 = 3

Answer:

3 m/s^2

Explanation:

The equation you have to use is F=ma because the problem is a Newton's 2nd law problem.

Our known values are:

F ( Force ) = 12,000 N

m ( mass ) = 4,000 kg

a ( acceleration ) = ?

Now we plug in the known values into the equation and solve

F=ma

12,000=4,000a

We have to divide 4,000 by both sides to isolate the a value

12,000/4,000=4,000/4,000a

The 4,000s on the right of the equation cancel.

And 12,000 divided by 4,000 equals 3

The acceleration (a) is 3 meters per second squared (m/s^2)

Next, check to make sure 3 does work by plugging it back into the equation.

12,000=4,000*3

12,000=12,000 ✔

As you can see, the acceleration will be 3 m/s^2

Answer: True

Explanation: "The lens is a transparent biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina."

Answer:

fem = 7.58 10⁻⁵ V

Explanation:

For this exercise we use Faraday's law

          fem =   [tex]- \frac{d \Phi _B}{dt}[/tex]

the magnetic flux is

          Ф_B = B. A = B A cos θ

Tje bold are vectros.  Suppose the case where the normal to the surface of the red blood cell is parallel to the field, therefore the angle is zero and the cos 0 = 1

The red blood cell area is

          A =π r²

indicate that the diameter is r = 8.00 mm = 8.00 10⁻³ m

the magnetic field has a frequency of f=60 Hz, and B₀ = 1.00 10⁻³T,  therefore we can write it

          B = B₀ sin (wt) = B₀ sin( 2π f t)

we substitute

           fem = - A dB / dt

           fem = - A B₀  [tex]\frac{ d (sin ( 2\pi f t)}{dt}[/tex]

           fem = - π r² Bo (2πf  cos 2πft)

the maximum electromotive force occurs when the function is ±1

           fem = 2 π² r² B₀ f

let's calculate

           fem = 2π²  (8.00 10⁻³)²  1.00 10⁻³ 60

           fem = 7.58 10⁻⁵ V

Answer:

Farsighted

Explanation:

Farsightedness also known as hypermetropia is caused by the eye being too short(the eye shortens with advancing age) or the crystalline lines not being sufficiently convergent.

A farsighted person can see far objects but can not see nearby objects. His near point is now farther than the 25 cm near point of a normal eye. Images are formed some distance behind the retina.

This eye defect is corrected by the use of a converging lens to reduce the divergence of the rays entering the eye from an object.

Answer:

B or 2

Explanation:

Answer:

(a)

W_friction = 98.1 J

W_net = 550.9 J

(b)

W_friction = 98.1 J

W_net = 463.95 J

Explanation:

(a)

First, we will calculate the work done by friction:

[tex]W_{friction} = \mu R = \mu W = \mu mg\\W_{friction} = (0.2)(50\ kg)(9.81\ m/s^2)\\[/tex]

W_friction = 98.1 J

Now, the work done by Eskimo will be:

[tex]W_{Eskimo} = FdCos\theta\\W_{Eskimo} = (110\ N)(5.9\ m)Cos\ 0^o\\[/tex]

W_Eskimo = 649 J

So, the net work will be:

W_net = W_{Eskimo} - W_{friction}

W_net = 649 J - 98.1 J

W_net = 550.9 J

(b)

First, we will calculate the work done by friction:

[tex]W_{friction} = \mu R = \mu W = \mu mg\\W_{friction} = (0.2)(50\ kg)(9.81\ m/s^2)\\[/tex]

W_friction = 98.1 J

Now, the work done by Eskimo will be:

[tex]W_{Eskimo} = FdCos\theta\\W_{Eskimo} = (110\ N)(5.9\ m)Cos\ 30^o\\[/tex]

W_Eskimo = 562.05 J

So, the net work will be:

W_net = W_{Eskimo} - W_{friction}

W_net = 562.05 J - 98.1 J

W_net = 463.95 J

Answer:

Anomalies are important because allow us to question if the experiment was carried out properly and if its method can also lead to other observations than the ones stated by the scientist. Anomalies are essential to learn more about a single experiment and improve the way ivestigation is done professionally.

Explanation:

Answer: Q= QH - QL

= W + QL - QL

= W

= 1 kj/8

Explanation:

Since the net rate is positive the room will be heated.

Answer:

The hot coffee has a higher temperature, but not a greater internal energy. Although the iceberg has less internal energy per mass, its enormously greater mass gives it a greater total energy than that in the small cup of coffee.

Explanation:

Answer:

The hot coffee has a higher temperature, but not a greater internal energy. Although the iceberg has less internal energy per mass, its enormously greater mass gives it a greater total energy than that in the small cup of coffee.

Answer:

Both.

Explanation:

Given that a block and a ball have the same mass and move with the same initial velocity across a floor and then encounter identical ramps. The block slides without friction and the ball rolls without slipping. 1)Which one makes it furthest up the ramp ?

Since both of them have the same mass and the same initial velocity, then, they will both have the same kinetic energy.

That is,

K.E = 1/2mv^2

Friction is a force that opposes motion. And since the frictional force is zero,

Both of them will accelerate from Newton's law.

F = ma

We can therefore conclude that both of them will make it further up the ramp.

Answer:

Explanation:

you can say the law of superpoition can tell us that each rock layer is older than the one above it. So, the relative age of the rock or fossil in the rock or fossil in the rock is older if it is farther down in the rock layers. hope it helps

Answer:

200 meters

Explanation:

20 x 10 = 200

Answer:

D. The object moves away from the origin at a speed of 3 m/s, stands still 6 m away from the origin for 3 seconds, then moves toward the origin at a speed of 2 m/s.

Explanation:

I just got it right lol