a object 1.5cm high produces a real image 2cm high. placed at a distance of 20cm
from a concave mirror calculate: [a] the position of the image [b] focal lenght of the concave mirror

The answer is:

-5846.75

Answer:

The sound travels differently in different medium according the density of the medium.

Explanation:

The sound travels faster in dense medium and can be heard by the vibration of the bone present in the ear. The ear plugs reduce the sound intensity in both medium water and on land (air).

In air the sound is not heard properly due to the earplugs that stops the as the vibration are not able to produce as sound is not able to reach to middle ear, but Navy researchers have discovered that sound under water is heard by the bone present behind the ear, vibrations mastoid.

Answer:

a) Strings of guitar (being played)

b) Heart-beat in a healthy person

c) Motion of an apple falling from a tree

Explanation:

a) The motion of the string of a guitar being played is the only motion involving simple harmonic motion.

b) All the other motions are circular motion except the heart beat in a healthy person, which is periodic.

c) The motion of an apply falling from a tree is the only motion under the complete influence of gravity from the onset till the end.

Answer:

The maximum torque, τ = 3.67 × 10⁻³ Nm

Explanation:

The torque τ = NiABsinθ where N = number of turns of circular coil = 50.5, i = current in circular coil = 22.5 mA = 0.0225 A, A = area of circular coil = πr² where r = radius of circular coil = 4.75 cm = 0.0475 m, B = magnetic field strength = 0.455 T and θ = 90° for maximum torque.

So, τ = NiABsinθ

τ = Niπr²Bsinθ

τ = 50.5 × 0.0225 A × π × (0.0475 m)² × 0.455 T × sin90°

τ = 0.003665 Nm

τ = 3.665 × 10⁻³ Nm

τ ≅ 3.67 × 10⁻³ Nm

So the maximum torque, τ = 3.67 × 10⁻³ Nm

Answer:

10.44° per sec

Explanation:

Initial angular speed N = 2 rotations per minute

converting to rad/s ω = 2πN/60 = (2 x 3.142 x 2)/60 = 0.21 rad/s

the initial radius of the disk = 16 cm = 0.16 m

final radius = 17 cm = 0.17 m

Angular momentum = [tex]I[/tex]ω

where [tex]I[/tex] = rotational inertia = mass x [tex]radius^{2}[/tex]

ω = angular speed

For the initial case

[tex]I[/tex] = m x [tex]0.16^{2}[/tex] = 0.0256m

Angular momentum = 0.0256m x 0.21 = 0.0054m

For second case

[tex]I[/tex] = m x [tex]0.17^{2}[/tex] = 0.0289m

Angular momentum = 0.0289m x ω = 0.0289mω

For conservation of rotational momentum, initial angular momentum must be equal to the final angular momentum

0.0054m = 0.0289mω

m cancels out, we have

0.0054 = 0.0289ω

ω = 0.187 rad/s

converting back to rpm, we have

N = 0.187/2π = 0.029 rotations per sec

0.029 x 360 = 10.44° per sec

Answer:

C. Heat flows from lemonade to the ice

Explanation:

Transfer of heat from the drink to the ice is what melts the ice and cools the drink.

Answer:

Thomson’s model

Explanation:

Thompson regarded the atom largely as a sphere of positively charged matter in which negative charges were embedded.

This came to be known as the plum pudding model of the atom because it resembles a pudding studded with currants.

This was an early model of the atom and did not survive further experimental scrutiny of the structure of the atom.

Answer:

Thompsons model

Explanation:

i got it right on the quiz

Answer:

t = 160 minutes

Explanation:

Given that,

Distance of Uranus from Sun is [tex]2.88\times 10^9\ km[/tex]

We need to find the time taken by the light to go from sun to Uranus if the velocity of light is constant in free space and it is equal to c.

So,

[tex]t=\dfrac{d}{v}\\\\t=\dfrac{2.88\times 10^9\times 10^3\ m}{3\times 10^8}\\\\t=9600\ s[/tex]

Since, 1 minute = 60 seconds

t = 160 minutes

So, 160 minutes is taken by the light.

Answer:

[tex]\large \boxed{\mathrm{40 \ Nm}}[/tex]

Explanation:

[tex]\sf Moment \ (Nm) = Force \ (N) \times Distance \ from \ pivot \ (m)[/tex]

[tex]M=20 \times 2[/tex]

[tex]M=40[/tex]

Answer:

A. to eat a healthier meal

Explanation:

The answer would be A, to eat a healthier meal. Eating a serving of mixed greens can enable Ben to shed pounds in the event that it encourages you to diminish your aggregate calorie admission. Pick filling fixings with the goal that you are not as ravenous and eat less, and keep your plates of mixed greens low in calories so they give fewer calories than the feast or tidbit that they are supplanting.

Answer:

Stroke has two emissions it could either be the meaning of lightly passing over something with the sense of touch for example stroking a dog/cat

And the medical term stroke where either a person has lost facial features of can't lift their arms up and keep them up or speak properly and their speech would be slurred

Hope this helps

If anything didn't meet your question please comment what you are looking for and I may change my answer thank you :)

Explanation:

Answer:

scalar

Explanation:

pounds is a unit of mass, and mass is a scalar quantity.

if it was weight (in newtons) it would be a vector.

A 5000-pound car sitting in the last parking space in the block is a scalar quantity, not a vector quantity.

The scaler quantity is only the quantity having some amount of magnitude but not direction and vector quantity is that which consists of both magnitude and the direction with them.

In 5000 pound car sitting in the last parking space in the block, it has a magnitude of 5000 pounds but does not have any direction to move and it comes under the scalar quantity.

Therefore, a car has scalar quantity not vector if, a 5000-pound car sitting in the last parking space in the block.

Learn more about scaler quantity and vector quantity, here:

https://brainly.com/question/774036

#SPJ2

Explanation:

We need to find the quantum state of a particle can be specified by giving a complete set of quantum numbers (n,l, ml,ms).

We have the principal quantum number, n = 3

The value of l = n-1

l = 0,1,2,3

The value of [tex]m_l[/tex]

[tex]m_l=-l\ \text{to}\ +l\\\\m_l=-3,-2,-1,0,1,2,3[/tex]

The value of [tex]m_s[/tex]

[tex]m_s=\dfrac{-1}{2},\dfrac{+1}{2}[/tex]

Hence, this is the required solution.

Answer:

30 miles people hour (mph)

Explanation:

The maximum speed for one flat tyre is 30mph, for both tyres it is 20 mph and for two tyres on the same side it is 30mph. When a tyre is punctured driving at high speed should be avoided and not too long distance should be covered to avoid further accident and for the safety of other vehicles. Speed limit and distance for flat tires should be strictly followed.

Answer:

Electronic tools provide more accurate data and this data is more efficient fast and easy to understand

Hope this helps you!!

Answer:

Artery and viens

Explanation:

Answer:

F.I.T.T. stands for frequency, intensity, time and type. These four key aspects of your workout program will help you achieve your athletic goal, whether it's to increase your endurance, strength or speed. Here is an in-depth look at what each means and how to modify it to make athletic gains on the field...

Answer:

maximum  point  y= 2R

 vₓ = wR ,  v_{y} = 0, aₓ = 0,  a{y} = - Rw²

minimum point   y=R

vₓ = wR , v_{y} = - R w,  aₓ = - R w²,  a_{y} = 0

Explanation:

The definition of velocity is

        v = dr / dt

        vₓ = dx / dt

        [tex]v_{y}[/tex] = dy / dt

        vₓ = Rw cos wt + wR

        v_{y} = -Rw sin wt

acceleration is defined by

         a = dv / dt

         aₓ = -Rw² sin wt

         a_{y} = - R w² cos wt

these are the general expressions for velocity and acceleration, to find the explicit values ​​for the maximum and minimum y points, let's find these points and substitute

maximum  point

         y = R cos wt + R

the heat is maximum when the cosine is worth 1

         y_max = 2R

at this point the speed is

         vₓ = wR

         v_{y} = 0

the acceleration is

         aₓ = 0

         a_{y} = - Rw²

minimum point

        this occurs when the cosine is zero

        y = R

speed is

       vₓ = wR

       v_{y} = - R w

acceleration is

        aₓ = - R w²

        a_{y} = 0

Answer:

6.0×10⁻²¹ J

Explanation:

KE = 3/2 kT,

where KE is average kinetic energy per molecule,

k is the Boltzmann constant,

and T is absolute temperature.

KE = 3/2 (1.38×10⁻²³ J/K) (18 + 273.15) K

KE = 6.0×10⁻²¹ J

Answer:

The answer is 6.0×10⁻²¹ J , because KE = 3/2 kT,  where KE is average kinetic energy per molecule,  k is the Boltzmann constant,  and T is the absolute temperature.

KE = 3/2 (1.38×10⁻²³ J/K) (18 + 273.15) K

KE = 6.0×10⁻²¹ J

Answer:

Ra, 88

Ru, 44

Cr, 24

Explanation:

i

the remaining mass number is 224(228 - 4), and it's atomic number is 88(90 - 2). The element is Radium, Ra

ii

the remaining mass number is 98(98 - 0), and it's atomic number is 44(45 - 1). The element is Ruthenium, Ru

iii

The remaining mass number is 52(52 - 0), and it's atomic number is 24(23 - -1). The element is Chromium, Cr

Answer:

If max height = 1.1 meters, then initial velocity is 3.28 m/s

If max height is 1.1 feet, then the initial velocity is 5.93  ft/s

Explanation:

Recall the formulas for vertical motion under the acceleration of gravity;

for the vertical velocity of the object we have

[tex]v=v_0-g \,t[/tex]

for the object's vertical displacement we have

[tex]y-y_0=v_0\,t - \frac{g}{2} \,t^2[/tex]

If the maximum height reached by the object is given in meters, we use the value for g in [tex]m/s^2[/tex] which is: [tex]9.8\,\,m/s^2[/tex]

If the maximum height of the object is given in feet, we use the value for g in  [tex]ft/s^2[/tex]  which is : [tex]32\,\,ft/s^2[/tex]

Now, when the ball reaches its maximum height, the ball's velocity is zero, so that allows us to solve for the time (t) the process of reaching the max height takes:

[tex]v=v_0-g \,t\\0=v_0-g \,t\\g\,\,t=v_0\\t=\frac{v_0}{g}[/tex]

and now we use this to express the maximum height in the second equation we typed:

[tex]y-y_0=v_0\,t - \frac{g}{2} \,t^2\\max\,height=v_0\,(\frac{v_0}{g}) - \frac{g}{2} \,(\frac{v_0}{g})^2\\max\,height= \frac{v_0^2}{2\,g}[/tex]

Then if the max height is 1.1 meters, we use the following formula to solve for [tex]v_0[/tex]:

[tex]1.1= \frac{v_0^2}{2\,9.8}\\(9.8)\,(1.1)=v_0^2\\v_0=10.78\\v_0=\sqrt{10.78} \\v_0=3.28\,\,m/s[/tex]

If the max height is 1.1 feet, we use the following formula to solve for [tex]v_0[/tex]:

[tex]1.1= \frac{v_0^2}{2\,32}\\(32)\,(1.1)=v_0^2\\v_0=35.2\\v_0=\sqrt{35.2} \\v_0=5.93\,\,ft/s[/tex]

Answer:

11

Explanation:

for khan academy, this is the answer

Answer:

4.5 x 10^4 x -2 x 10^-6 = -0.09N

Explanation:

-0.09N

Answer:

[tex]t = 0.75 \ hr = 0.75 *60 = 45 \ minutes[/tex]

Explanation:

From the question we are told that

   The  hydraulic conductivity is  [tex]Ks = 10\ mm/hr[/tex]

    The  effective matrix potential [tex]Ns = 20 \ mm[/tex]

    The  intensity of  rainfall is  [tex]I = 30 \ mm/hr[/tex]

    The runoff rate [tex]R = 15 \ mm/hr[/tex]

Generally the run off rate is mathematically represented as  

      [tex]R = (I - Ks) t[/tex]

Here t is the amount of runoff generated

=>   [tex]15 = (30 - 10) t[/tex]

=>  [tex]t = 0.75 \ hr[/tex]

converting to minutes

    [tex]t = 0.75 \ hr = 0.75 *60 = 45 \ minutes[/tex]

Answer:

you live it will be around 23 to 82% angle

Explanation:

just think about yourself going in the high-speed and then jumping and then just think of all know that person just jumping without being going to high speed

mass of an object is always constant

weight is a force, [tex]W=mg[/tex] where $g$ is acceleration due to gravity.

Weight on earth is , $900=m\cdot 10 \implies m=90$ kg

weight on moon is $150=90\times g_{\text{moon}} \implies g=\frac{5}{3}$

Answer:

Answer c: "when particles in matter gain or lose energy , they change state"

Explanation:

As energy is provided to the molecules of the substance in question, they acquire more speed or vibration, increasing their separation in the substance, which can become then a liquid , or a gas. The reverse path also happens as the particles give away energy.

Answer:

c. when particles in matter gain or lose energy , they change state

we know that for example, if you add heat (energy) to ice it would melt (change state) or if you freeze water (change state) it would become ice.

Answer:

R=4Ω

Explanation:

R1 and R3 are parrallel

so we have : R=R1*R2/R1+R2

R=6*3/6+3

R=18/9

R=2Ω

R2 and 2Ω are in series,so we have

R=R2+2

R=2+2

R=4Ω

Answer:

1.05×10⁻⁴ m²

Explanation:

ΔA = 2 A₀ α ΔT,

where ΔA is the change in area,

A₀ is the initial area,

α is the linear expansion coefficient,

and ΔT is the change in temperature.

A₀ = π (0.20 m / 2)² = 0.0314 m².

For steel, α = 13×10⁻⁶ /°C.

ΔT = 150°C − 22°C = 128°C.

ΔA = 2 (0.0314 m²) (13×10⁻⁶ /°C) (128°C)

ΔA = 1.05×10⁻⁴ m²

Answer:

50m/s.

Explanation:

Let's take acceleration as A and speed as S:

A = 5m/s²

S = A × 10s = 5 × 10 = 50m/s

The answer is 50m/s.

Answer:

50m/s

Explanation:

Given:

a=5m/s^2

t=10s

Required:

v=?

Formula:

a=v/t

Solution:

a=v/t

v=a*t

v=5m/s^2*10s

v=50m/s

Hope this helps ;)❤❤❤

Answer:

0.25 m/s

Explanation:

Average velocity = change in displacement / change in time

v = (1.5 m − 2.5 m) / (6 s − 2 s)

v = -0.25 m/s

The average speed is 0.25 m/s.

Answer:

0.25 m/s

Explanation:

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