an object is placed in front of a spherical mirror of focal length -20 cm at a distance of 30cm. at what distance from the mirror a screen should be placed in order to get a sharp image of the object

Answer:

to prevent food spoilage until it can be consumed

Explanation:

 Gardens often produce too much food at one time—more than can be eaten before spoilage sets in. Preserving food also offers the opportunity to have a wide variety of foods year-round. It's economic.

The total electric field produced by the charges at the midpoint is

8 x 10³ N/C.

Amount of charge on the first particle, q₁ = 40 x 10⁻⁹C

Amount of charge on the second particle, q₂ = 60 x 10⁻⁹C

Distance between the charges, r = 30 cm = 0.3 m

The expression for the electric field due to the charges is given by,

E = 1/4πε₀ x q/r²

At the midpoint between the two charges, d = 0.15 m

So, the electric field produced by the charge q₁ at the midpoint is,

E₁ = 1/4πε₀ x q₁/d²

E₁ = 9 x 10⁹ x 40 x 10⁻⁹/(0.15)²

E₁ = 1.6 x 10⁴ N/C

So, the electric field produced by the charge q₂ at the midpoint is,

E₂ = 1/4πε₀ x q₂/d²

E₂ = 9 x 10⁹ x 60 x 10⁻⁹C/(0.15)²

E₂ = 2.4 x 10⁴ N/C

Therefore, the total electric field produced by the charges at the midpoint is,

E = E₂ - E₁

E = 2.4 x 10⁴- 1.6 x 10⁴

E = 8 x 10³ N/C

To learn more about electric field, click:

https://brainly.com/question/30544719

#SPJ1

The activation energy for the diffusion process of Al in Al2O3 is approximately 225,744 J/mol.

To calculate the activation energy for the diffusion process of Al in Al2O3, we can use the Arrhenius equation:

D = D0 * exp(-Q/RT)

where D is the diffusion coefficient, D0 is a constant, Q is the activation energy, R is the gas constant, and T is the absolute temperature.

Taking the natural logarithm of both sides, we get:

ln(D/D0) = -Q/RT

We can then use the given diffusion coefficients and temperatures to obtain two equations:

ln(D1/D0) = -Q/RT1

ln(D2/D0) = -Q/RT2

where D1 and T1 are the diffusion coefficient and temperature at 1000C, and D2 and T2 are the diffusion coefficient and temperature at 1500C.

Taking the ratio of the two equations, we get:

ln(D2/D1) = Q/R * (1/T1 - 1/T2)

Solving for Q, we get:

Q = -R * ln(D2/D1) / (1/T1 - 1/T2)

Plugging in the given values, we get:

Q = -8.314 J/mol-K * ln(2.48 x 10^-14 m^2/s / 7.48 x 10^-23 m^2/s) / (1/1273 K - 1/1773 K)

Q ≈ 225,744 J/mol

Therefore, the activation energy for the diffusion process of Al in Al2O3 is approximately 225,744 J/mol.

For more question on activation energy

https://brainly.com/question/15083463

#SPJ11

The average speed of the campers down the river was 5 miles per hour.

Total distance traveled by the campers = 25 miles

Total time taken by the campers = 5 hours

Speed is defined as the rate of change in distance or altitude reached. It is a time-based quantity. In the given question, a camper's average speed can be calculated by dividing the total distance travelled by the time taken.

Calculating the average speed of the campers -

Average speed = Total distance / Time taken

Substituting the values -

= 25 miles / 5 hours

= 5

Read more about speed on:

https://brainly.com/question/24739297

#SPJ1

Move numbers to the boxes to show the factor pairs of 14:

Blank space 1: 1

Blank space 2: 1

Blank space 3: 2

Blank space 4: 7

A factor pair of a number is a pair of whole numbers that can be multiplied together to give the original number. For the number 14, the factor pairs are (1,14) and (2,7). So, we can put 1 in the first blank, 14 in the second blank, 2 in the third blank, and 7 in the fourth blank to show the factor pairs of 14.

To show the factor pairs of 14 in the given response area with 4 blank spaces, we need to find the two numbers that can be multiplied together to give 14. These two numbers are called factor pairs of 14.

To begin, we can start listing the factors of 14. The factors of 14 are 1, 2, 7, and 14. We can then use these factors to form factor pairs by multiplying them together. The factor pairs of 14 are (1, 14) and (2, 7).

To show these factor pairs in the given response area, we can put the first factor of each pair in the first and third blank spaces, and the second factor of each pair in the second and fourth blank spaces. Therefore, we can put 1 in the first blank, 14 in the second blank, 2 in the third blank, and 7 in the fourth blank to show the factor pairs of 14.

Learn more about Whole numbers at

brainly.com/question/29766862

#SPJ1

The Falcon 9 rocket is so important in today's space exploration world because It's a reusable rocket and has saved money by being reused over 60 times already.

option D.

The Falcon 9 rocket, is developed by SpaceX, and it holds  a significant importance in today's space exploration world due to several key features and achievements, and some of the importance include the following;

From the given options, we can conclude that the Falcon 9 rocket is so important in today's space exploration world because It's a reusable rocket and has saved money by being reused over 60 times already.

Learn more about space exploration here: https://brainly.com/question/27325845

#SPJ1

A physical standard is a physical item used as a standard measurement

A physical standard is an object that is carefully designed, manufactured and maintained to serve as a reference or benchmark for measurements. It represents a specific quantity or characteristics with a well defined value, making it a point of comparison for other similar measurements. Physical standards are used in various fields, including science, engineering, metrology , and quality control.

Physical standards can take different forms depending on the quantity being measured. For a example a standard kilogram represent the unit of mass and a standard meter represent unit of length.

Learn more about physical measurement standard below.

https://brainly.com/question/17262133

#SPJ1

A parallel circuit can be modelled by connecting the components parallel.

A parallel circuit is a form of electrical circuit in which the components are linked in parallel to one another, each having a separate channel for current flow and being directly connected to the power source. The circuit must first be schematically represented, with the power supply and each component linked in parallel. Next, the total resistance the total current in the circuit by using Ohm's Law must be calculated.

Additionally, it is necessary to confirm that the total current entering the circuit equals the total current leaving the circuit. In a parallel circuit, the total current passing through all of the components equals the current entering the circuit. The voltage drop between each component must then be once more computed using Ohm's Law.

Read more about parallel circuits on:

https://brainly.com/question/19929102

#SPJ1

To calculate the average speed of the car, we can use the formula:

Average speed = Total distance / Total time

Given information:

Number of laps = 60

Track length per lap = 3.6 km

Total time = 2.4 hours

First, let's calculate the total distance traveled by the car:

Total distance = Number of laps * Track length per lap

Total distance = 60 * 3.6 km

Total distance = 216 km

Now, we can calculate the average speed:

Average speed = Total distance / Total time

Average speed = 216 km / 2.4 hours

Average speed ≈ 90 km/h

So, the average speed of the car is approximately 90 km/h.

If the coefficient of kinetic friction between Josh's sled and the snow is 0.08, he slides 6.97 meter from the base of the hill.

To find how far from the base of the hill Josh's sled ends up, we need to first find the speed of the sled at the bottom of the hill using the conservation of energy principle,

mgh = (1/2)mv², plugging in the values given in the problem, we get,

m(9.81 m/s²)(3.5 m) = (1/2)mv²

Simplifying and solving for v, we get,

v = √(2gh)

v = √(2(9.81 m/s²)(3.5 m))

v = 8.29 m/s

Now we can use the kinematic equation,

d = vt - (1/2)at, to find how far the sled slides on the horizontal patch of snow before coming to a stop, where d is the distance traveled, v is the initial velocity (8.29 m/s), a is the acceleration due to friction (-μg), and t is the time it takes to come to a stop (which we can find by setting v = 0 and solving for t),

0 = 8.29 m/s - μg*t

t = 8.29 m/s / μg

Substituting this value of t back into the kinematic equation, we get,

d = (8.29)(8.29/μg) - (1/2)μg(8.29/μg)²

d = 6.97 m

Therefore, Josh's sled ends up 6.97 meters from the base of the hill.

To know more about energy conservation principle, visit,

https://brainly.com/question/24772394

#SPJ1

(a) The  force pulling the apple is the weight of the apple and the magnitude is determined as 0.98 N.

(b) The gravity needed is 0.98 N.

(c) The energy transfer that takes place is 5.88 J.

The gravity needed is calculated as follows;

Fg = mg

where;

Fg = 0.1 x 9.8

Fg = 0.98 N

The  force pulling the apple is equal in magnitude to force of gravity and the magnitude is determined as 0.98 N.

So the pulling force on the apple is the weight of the apple.

The energy transfer that takes place is calculated as follows;

E = P.E = mgh

E = 0.98 N x 6 m

E = 5.88 J

Learn more about force of gravity here: https://brainly.com/question/2537310

#SPJ1

Answer: [tex]f=3.125 Hz[/tex]

Explanation:

frequency = 1 / period

[tex]f=\frac{1}{T}[/tex]

[tex]f=\frac{1}{0.32}=3.125Hz[/tex]

Therefore, the frequency of the wave is 3.125 Hz.

the physics of a domino chain shows how momentum and kinetic energy can combine to produce an amazing display of dominoes falling.

First of all, momentum is a vector that denotes an object's mass and speed. When a domino chain is pushed over, the initial domino that was knocked over transfers momentum to the next domino, which then transfers momentum to the next, and so on. Each domino does not have to travel at the same pace as the others as long as they are in time with one another since the group of dominoes offers a coordinated transfer of momentum.

The second definition of kinetic energy is the energy that an item has as a result of motion. Kinetic energy increases each domino's speed and the power necessary to topple the subsequent domino in a chain of dominoes as momentum is transferred from one domino to the next. The largest domino, which frequently topples onto a designated catch or platform that intensifies the effect for spectators, is where the chain's greatest amount of kinetic energy is stored when it reaches its conclusion.

To know more kinetic Energy :

https://brainly.com/question/26405082

#SPJ1.

A and B are the correct statements. A. The ‘Moon’ should be 240 steps away from the ‘Earth’. The ‘Earth’ should be 93 steps away from the ‘Sun’.

To create a model of the distances between the Earth, the Moon, and the Sun, we represent one million miles with one step. Based on this model:

A. The ‘Moon’ should be 240 steps away from the ‘Earth’. This is a correct statement, as the distance between the Earth and the Moon is about 240 thousand miles. In the model, we represent each million miles with one step, so the distance between the Earth and the Moon in the model would be 240 steps.

B. The ‘Earth’ should be 93 steps away from the ‘Sun’. This is also a correct statement, as the distance between the Earth and the Sun is about 93 million miles. In the model, we represent each million miles with one step, so the distance between the Earth and the Sun in the model would be 93 steps.

C. The ‘Moon’ should be less than one step away from the ‘Earth’. This statement is incorrect, as the actual distance between the Earth and the Moon is much greater than one million miles. In the model, the distance between the Earth and the Moon would be represented by 240 steps.

D. The ‘Earth’ should be 5 steps away from the ‘Sun’. This statement is incorrect, as the actual distance between the Earth and the Sun is much greater than five million miles. In the model, the distance between the Earth and the Sun would be represented by 93 steps.

For more question on Earth

https://brainly.com/question/27943482

#SPJ11

Gore argues that the combination of population growth, a globalized economy, and technological impact is driving our civilization towards a collision with the Earth, jeopardizing the well-being of future generations.

1. Population Growth: Gore argues that the rapid growth of the global population is straining the Earth's resources and ecosystems. As the population increases, so does the demand for food, water, energy, and other resources, leading to overconsumption and environmental degradation. This places a significant burden on the planet's capacity to sustain life and maintain a healthy balance.

2. Globalized Economy: The expansion of the globalized economy has resulted in increased production, consumption, and trade on a massive scale. While this has brought economic benefits and improved living standards for many, it has also contributed to environmental problems. The pursuit of economic growth often prioritizes short-term profits over long-term sustainability, leading to resource depletion, pollution, and climate change.

3. Technological Impact: Advances in technology have brought numerous benefits to society, but they have also come with unintended consequences. Industrial processes, transportation systems, and energy production have increasingly relied on fossil fuels, leading to greenhouse gas emissions and climate change. Additionally, technological advancements have accelerated the extraction and exploitation of natural resources, further straining the planet's ecosystems.

He advocates for sustainable solutions that prioritize environmental conservation, renewable energy, and responsible resource management to mitigate these challenges.

For such more questions on collision

https://brainly.com/question/8863042

#SPJ11

If two buses are moving in the same direction with the same velocity, a passenger in one bus would perceive the other bus as being at rest relative to their own frame of reference. This phenomenon is known as relative motion or the principle of relativity.

The reason behind this perception is that both buses are moving with the same velocity. From the perspective of the passenger in one bus, they are also moving at the same speed and in the same direction as their own bus. Therefore, the relative velocity between the two buses is zero, and the passenger perceives the other bus as being stationary.

This perception is similar to how passengers inside a moving train may perceive nearby objects, such as other stationary trains on parallel tracks, as being at rest relative to their own moving train. It's important to note that this perception of relative rest is valid only within the frame of reference of the passenger in one bus. Observers outside the buses, or in a different frame of reference, would see both buses moving with the same velocity.

For more such questions on Relative motion

https://brainly.com/question/17228388

#SPJ11

Answer:

Charged

Explanation:

When an atoms loses or gains electrons they become charged(ion)

When an atom loses electrons it becomes positively charged and it is called a Cation

When an atom gains electrons it becomes negatively charged and it is called an Anion

a negative charge Q1 = -5.50 is located at a point x1=-6.00 abd. positive charge Q2= 6.50 uc is located at point x2= 4.00 m then the magnitude and direction of the electric force between the charges is 3.56 mN and from left to right.

Coulomb's Law, which says that the electric force between two charges is directly proportional to the product of their charges and inversely proportional to the square of their distance, may be used to determine the size and direction of the electric force between the provided charges.

Given:

Q1 = -5.50 μC (negative charge)

Q2 = 6.50 μC (positive charge)

x1 = -6.00 m (position of Q1)

x2 = 4.00 m (position of Q2)

distance between the charges is

Distance (d) = |x2 - x1| = |4.00 m - (-6.00 m)| = 10.00 m

electric force (F) by using Coulomb's Law:

F = (k * |Q1| * |Q2|) / (d^2)

Where k is the electrostatic constant, which is equal to 9 × 10^9 N·m^2/C^2.

Substituting the given values:

F = (9 × 10⁹ N·m²/C² * |(-5.50 μC)| * |6.50 μC|) / (10.00 m)^2

F ≈ 3.2 mN

The magnitude of the electric force between the charges is approximately 3.56 mN.

Since Q1 is negative and Q2 is positive, the electric force acts in the direction from Q1 towards Q2. Therefore, the direction of the electric force is from left to right.

To know more about Electric Force :

https://brainly.com/question/31696602

#SPJ1.

According to the information, the steel ring should be heated to a maximum temperature of approximately 50.67°C to enable fitting; and the stresses in the materials on cooling will be approximately 17.04 MPa in the steel ring and 2.11 MPa in the brass wheel.

To enable fitting, the steel ring needs to expand in size so that its inner diameter matches the outer diameter of the brass wheel. We can use the formula for linear thermal expansion:

Where ΔL is the change in length, α is the coefficient of linear expansion, L0 is the initial length, and ΔT is the change in temperature. By substituting the given values and solving for ΔT, we find that the steel ring needs to be heated to a maximum temperature of approximately 50.67°C.

The stresses in the materials can be calculated using the formula:

Since the dimensions of the cross-sections are given, we can calculate the areas of the steel ring and brass wheel. The force can be calculated using the equation:

By substituting the given values for Young's modulus, change in length, and initial length, we can calculate the forces in both materials. Finally, by dividing the forces by their respective areas, we can determine the stresses in the steel ring and brass wheel, which are approximately 17.04 MPa and 2.11 MPa, respectively.

Learn more about materials in: https://brainly.com/question/27403649

#PSJ1

The magnitude of the frictional force is 5 N.

The force exerted by the boy on the box is 40.0 N. According to Newton's second law of motion, the net force acting on an object is equal to the product of its mass and acceleration:

F(net) = m*a

where F(net) is the net force, m is the mass of the object, and a is its acceleration.

In this case, the net force acting on the box is the force applied by the boy minus the frictional force:

F(net) = F(applied) - F(friction)

By substituting the values:

F(applied) = 40.0 N

m = 5 kg

a = 7 m/s^2

Now, by using frictional force:

F(friction) = F(applied) - F(net)

F(friction) = F(applied) - ma

                = 40.0 N - (5 kg)(7 m/s^2)

                = 5 N

To know more about frictional force refer to:

brainly.com/question/31125218

#SPJ1

The required acceleration of the car, when the driver hits the brake, is [tex]-5 m/s^2[/tex], the negative sign indicates that the car is slowing down.

From the question we can see that the:

initial velocity(u) is + 100 m/s (to the right)

Final velocity (v) is 0 since the car comes to stop

Time (t) is 20 s

We can use the formula

a= (v-u)/t to find the acceleration(a) of the car.

Now Substituting the values in the formula given above we get:

a=(0-100)/20

a= [tex]-5m/s^2[/tex]

Therefore, the acceleration of the car is [tex]-5 m/s^2[/tex]. The negative sign in the answer indicates that the acceleration is in the opposite direction to the initial velocity, which means that the car is slowing down or decelerating.

Learn more about acceleration at:

https://brainly.com/question/26246639

#SPJ1

The metal with the highest heat capacity between metals A.25 B.35 C.10 and D.15 is metal A.

Heat capacity is the amount of heat required to raise the temperature of a substance by one degree Celsius. Metal A has a heat capacity of 400 J/kg°C, which means that it takes 400 joules of heat to raise the temperature of one kilogram of metal A by one degree Celsius.

Metal B has a heat capacity of 285.7 J/kg°C, metal C has a heat capacity of 1000 J/kg°C, and metal D has a heat capacity of 666.7 J/kg°C. Therefore, metal A has the highest heat capacity of the four metals.

Metal A's high heat capacity means that it can absorb a lot of heat without its temperature changing very much. This makes metal A a good material for things like heat sinks and thermal insulation.

Find out more on heat capacity here: https://brainly.com/question/16559442

#SPJ1

There are a few formulas you can use to calculate final velocity, depending on the information given:

If given initial velocity, acceleration, and time, use:

vfinal = vinitial + at

Where:

vfinal is the final velocity

vinitial is the initial velocity

a is the acceleration

t is the time

If given initial velocity, change in velocity, and time, use:

vfinal = vinitial + Δv

Where:

Δv is the change in velocity

If given displacement, initial velocity, acceleration, and time, use:

vfinal = √(vinitial2 + 2aΔx)

Where:

Δx is the displacement

If given initial and final displacements and time, use:

vfinal = Δx/t

So in summary, to calculate final velocity you need:

Initial velocity + Acceleration + Time

OR

Initial velocity + Change in velocity

OR

Initial velocity + Acceleration + Displacement + Time

OR

Initial/final displacement + Time

Then you can use the appropriate formula, plug in the known values, and solve for final velocity (vfinal).

Hope these formulas and explanations help! Let me know if you have any other questions.

The circuit given is a series resistance circuit.

1) The given circuit is a series resistance circuit.

2) Resistance, R₁ = 20 Ω

Resistance, R₂ = 5 Ω

The effective resistance of the circuit is given by,

Reff = R₁ + R₂

Reff = 20 + 5

Reff = 25 Ω

3) Total resistance of the circuit, R = 25 Ω

Current flowing through the circuit, I = 50 A

Therefore, the voltage across the circuit is,

V = IR

V = 50 x 25

V = 1250 V

To learn more about series resistance circuit, click:

https://brainly.com/question/1851488

#SPJ1

The magnitude of the magnetic field's torque on the loop is 0.034 Nm.

When a current-carrying conductor is put in a magnetic field, it experiences a force known as the Lorentz force, which is proportional to the magnetic field's strength and the current running through the conductor. As a result of this force, a torque is imparted to the conductor, which tends to turn it around an axis perpendicular to the conductor's plane.

The following formula can be used to calculate the torque operating on the conductor:

= NIABsin

where is the torque, N is the number of turns, I is the current, A is the area of the loop, B is the strength of the magnetic field, and is the angle between the magnetic field and the plane of the loop.

If the magnetic field is parallel to the plane of the loop, then θ is equal to 0°, and sinθ is equal to 0.

As a result, the torque formula can be shortened to: = NIAB.

When the numbers for N, I, A, and B are entered into this formula, the magnetic field's torque on the loop is found to be:

= (1)(0.017 A)(π(1 m)²)(0.80 T)τ = 0.034 Nm.

As a result, the magnitude of the magnetic field's torque on the loop is 0.034 Nm.

For more such questions on torque, click on:

https://brainly.com/question/17512177

#SPJ8

Thermal expansion is defined as the property of metals to expand when they are heated.

The metal expands when heated because the atoms move apart more.

An excellent method to demonstrate the concept of thermal expansion is using the bar and gauge experiment.

Both the diameter and the length are precisely comparable when both are at room temperature.

The bar will not fit within the gauge once it has been heated and cooled. Similar to the last instance; the bar will no longer fit flush inside the gauge if the gauge is heated and the bar is cooled.

To learn more about thermal expansion, click:

https://brainly.com/question/14092908

#SPJ1

The observation that electromagnetic radiation with energy above a certain value can eject electrons out of a metal is a piece of evidence that they have particle-like properties.

The observation that electromagnetic radiation with energy above a certain value can eject electrons out of a metal is a piece of evidence that they have particle-like properties.

This observation that electromagnetic radiation behaves like particles is known as the photoelectric effect.

It provides evidence that electromagnetic radiation exhibits particle-like properties. When EMR with sufficient energy (above a certain threshold) interacts with a metal surface, it can cause the ejection of electrons from the metal.

This behavior indicates that EMR behaves as discrete packets of energy called photons, which transfer their energy to the electrons and cause their release. The photoelectric effect supports the particle nature of EMR and is a fundamental concept in the field of quantum mechanics.

More on electromagnetic radiation can be found here: https://brainly.com/question/29646884

#SPJ1

1. The substance equation for water is [tex]H_2O[/tex].

2. The compound name for table salt is sodium chloride [tex](NaCl)[/tex].

3. The synthetic equation for carbon dioxide is [tex]CO_2[/tex].

4. The substance name for baking soft drink is sodium bicarbonate [tex](NaHCO_3)[/tex].

5.  The substance recipe for methane is [tex]CH_4[/tex].

6. The compound name for vinegar is acidic corrosive [tex](CH_3COOH)[/tex]

7.  The compound equation for smelling salts is [tex]NH_3[/tex].

8. The compound name for blanch is sodium hypochlorite [tex](NaClO)[/tex].

9.  The synthetic equation for hydrogen peroxide is [tex]H_2O_2[/tex].

10. The synthetic name for rust is iron oxide [tex](Fe_2O_3)[/tex].

11.  The compound recipe for sodium hydroxide is [tex]NaOH[/tex].

12. The substance name for lye is sodium hydroxide [tex](NaOH)[/tex].

13. The synthetic equation for sulfuric corrosive is [tex]H_2SO_4[/tex].

14. The compound name for gypsum is calcium sulfate dihydrate [tex](CaSO_4.2H_2O)[/tex].

15. The substance equation for table sugar is [tex]C_1_2H_2_2O_1_1[/tex].

16. The synthetic name for anti-inflamatory medicine is acetylsalicylic corrosive [tex](C_9H_8O_4)[/tex].

17. The compound recipe for calcium carbonate is [tex]CaCO_3[/tex].

18. The substance name for baking powder is a combination of sodium bicarbonate [tex](NaHCO_3)[/tex] and an acidic fixing like cream of tartar [tex](KC_4H_5O_6)[/tex].

19. The synthetic equation for sodium chloride is [tex]NaCl[/tex].

20. The substance name for hydrogen gas is [tex]H_2[/tex].

The questions are:

1. What is the synthetic recipe for water?

2. What is the substance name for table salt?

3. What is the compound equation for carbon dioxide?

4. What is the synthetic name for baking pop?

5. What is the substance equation for methane?

6. What is the synthetic name for vinegar?

7. What is the substance equation for alkali?

8. What is the substance name for blanch?

9. What is the compound recipe for hydrogen peroxide?

10. What is the synthetic name for rust?

11. What is the synthetic equation for sodium hydroxide?

12. What is the synthetic name for lye?

13. What is the substance recipe for sulfuric corrosive?

14. What is the substance name for gypsum?

15. What is the synthetic recipe for table sugar?

16. What is the substance name for anti-inflamatory medicine?

17. What is the synthetic equation for calcium carbonate?

18. What is the synthetic name for baking powder?

19. What is the substance equation for sodium chloride?

20. What is the substance name for hydrogen gas?

For more such questions on hydrogen peroxide, click on:

https://brainly.com/question/25566753

#SPJ11

Answer: 3.8

Explanation: speed = wavelength x frequency