Let's say you want to start a fire using a mirror to focus sunlight. What would you do A) use a plane mirror. B) use a convex mirror , with the object to be ignited positioned at the center of curvature of the mirror. C) use a concave mirror, with the object to be ignited positioned at the center of curvature of the mirror. D) use a concave mirror, with the object to be ignited positioned halfway between the mirror and its center of curvature.

Answer:

B

A

Explanation:

please mark as brainliest :)

Answer: A.0,0097s

Mas a unidade aí deveria ser Hertz (Hz)

Explanation:

Answer:

103 hz

Explanation:

Answer:

m=6.25kg

Explanation:

Force= mass × acceleration

50=m×8

make m subject of the formula...

m=50/8

m=6.25kg

Answer:

[tex]\boxed {\boxed {\sf 6.25 \ kilograms}}[/tex]

Explanation:

According to Newton's Second Law of Motion, force is the product of mass and acceleration.

[tex]F= m \times a[/tex]

We know the force is 50 Newtons and the acceleration is 8 meters per second squared. Let's convert the units to make the problem and unit cancellation easier.

1 Newton is equal to 1 kilogram meter per square second (1 kg*m/s²), so the force of 50 N is equal to 50 kg*m/s².

Now we know 2 values:

Substitute the values into the formula.

[tex]50 \ kg *m/s^2= m \times 8 \ m/s^2[/tex]

Since we are solving for the mass, we must isolate the variable, m. It is being multiplied by 8 meters per square second and the inverse of multiplication is division. Divide both sides by 8 m/s².

[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= \frac{m \times 8 \ m/s^2}{8 \ m/s^2}[/tex]

[tex]\frac {50 \ kg *m/s^2}{8 \ m/s^2}= m[/tex]

The units of meters per square second (m/s²) cancel.

[tex]\frac {50 \ kg }{8 }=m[/tex]

[tex]6.25 \ kg =m[/tex]

The mass is 6.25 kilograms.

Answer:

the answer to the question is mitosis

Answer:

undergone a chemical change

Explanation:

Answer:

undergone a chemical change

Answer:

i. 2.5 kHz ii. 5 kHz

Explanation:

The frequency of the wave in the rod is given by f = nv/2L where n = harmonic, v = speed of sound in rod = 5000 m/s and L = length of rod = 1 m

i. f1

For f1, n = 1

f1 = 1 × v/2L

= v/2L

Substituting the values of the variables into the equation, we have

= 5000 m/s ÷ (2 × 1 m)

= 5000 m/s ÷ 2 m

= 2500 /s

= 2500 Hz

= 2.5 kHz

ii. f2

For f2, n = 2

f2 = 2 × v/2L

= v/L

Substituting the values of the variables into the equation, we have

= 5000 m/s ÷ 1 m  

= 5000 /s

= 5000 Hz

= 5 kHz

Answer:

A

Explanation:

moving a magnet into a coil of wire in a closed circuit

Craig, move a magnet into a coil of wire in a closed circuit for the discovery of electromagnetism. Option A is correct.

The physical interplay of electric charges, magnetic moments, and the electromagnetic field is known as electromagnetism.

The electromagnetic field can be static, moving slowly, or forming waves.

Craig, move a magnet into a coil of wire in a closed circuit for the discovery of electromagnetism.

Hence, option A is correct.

To learn more about the electromagnetism, refer to the link;

https://brainly.com/question/3427992

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Object name:- Rock

Starting energy:- Kinetic energy

Conversion:- Potential to kinetic energy

Final energy form:- Potential energy

Non usable form if energy:- Nil [ As it has potential & kinetic both]

Answer:

A

Explanation:

because she wants to practice science and A is the practical option.

Answer:

The solution is neither acidic or basic,

PH < 7    acidic

PH = 7    neutral

PH > 7 basic

It is a measure of the (H+) hydronium concentration.

Answer:

It’s stratosphere

Explanation:

Most ozone is found in a region of Earth’s atmosphere between 10 and 20 miles above Earth’s surface. This temperature zone of the atmosphere is known as the stratosphere.

Ozone is an allotrope of oxygen. It is blue in color and it is found in Earth's atmosphere. It protects the Earth from ultraviolet rays from the Sun.

The ozone subcaste is centered at an altitude between 10-15 country miles (15-25 km). Close to 90% of the ozone found in the atmosphere is in the stratosphere. Ozone that is found in this region is about 10 parts per million by volume (ppmv) to the troposphere's 0.04 ppmv.

Therefore, we have determined that Most ozone is found in a region of Earth’s atmosphere between 10 and 20 miles above Earth’s surface. This temperature zone of the atmosphere is known as the stratosphere.

Learn more about ozone here: https://brainly.com/question/26254261

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Charge = 0.2 Ah is the correct answer...

Answer:

Pressure = 39200 N/m²

Explanation:

Given the following data;

Mass = 60 kg

Area = 150 cm²

Conversion:

1 centimeter square = 0.0001 meter square

150 centimeter square = 150 * 0.0001 = 0.015 m²

To find the pressure exerted on the ground by the person;

Mathematically, pressure is given by the formula;

[tex] Pressure = \frac {Force}{area} [/tex]

First of all, we would determine the force exerted by the person.

Force = mass * acceleration due to gravity.

We know that acceleration due to gravity is equal to 9.8 m/s².

Substituting into the formula, we have;

Force = 60 * 9.8

Force = 588 Newton

Next, find the pressure;

[tex] Pressure = \frac {Force}{area} [/tex]

Substituting into the formula, we have;

[tex] Pressure = \frac {588}{0.015} [/tex]

Pressure = 39200 N/m²

Answer:

Water can spread germs through bacteria.

Explanation:

Bacteria can live in water and can spread to new locations when water is moved.

Answer:

Las estrellas se forman debido a la unión de pequeños elementos y partículas como el hidrógeno y el helio que experimentan una fusión nuclear en el núcleo debido a la intensa presión para formar un nuevo átomo (como dos hidrógeno que se combinan para formar un átomo de helio) que es un proceso. que requiere una gran cantidad de energía para comenzar, por lo que cada reacción de fusión produce una gran cantidad de energía que puede mantener la reacción y equilibra la fuerza gravitacional que atrae las masas de las partículas hacia el centro de la estrella

A medida que la energía de la estrella se irradia, la superficie de la estrella cede la energía en forma de calor y luz de manera que debido a la alta temperatura de las partículas de los átomos de los elementos se mueven muy rápida y energéticamente para emitir fotones rápidamente. (alta frecuencia) que se ve como el alto brillo de la estrella

Explanation:

Answer:

F = 2.45 N

Explanation:

m = 0.25 kg

a = 9.8 m/s^2

F = ma

F = (0.25)(9.8)

F = 2.45 N

Answer:

the answer is already there lol

Explanation:

Answer:

answer is there you can see from there lol

Explanation:

Answer:

Which of the following... : constant velocity horizontal motion

A ball is thrown at certain... : 0 m/s

Answer:

the kinetic energy lost due to friction is 22.5 J

Explanation:

Given;

mass of the block, m = 0.2 kg

initial velocity of the block, u = 25 m/s

final velocity of the block, v = 20 m/s

The kinetic energy lost due to friction is calculated as;

[tex]\Delta K.E= K.E_f - K.E_i\\\\\Delta K.E= \frac{1}{2}mv^2 - \frac{1}{2}mu^2\\\\\Delta K.E= \frac{1}{2}m(v^2 -u^2)\\\\\Delta K.E= \frac{1}{2} \times 0.2 (20^2 - 25^2)\\\\\Delta K.E= -22.5 \ J[/tex]

Therefore, the kinetic energy lost due to friction is 22.5 J

Answer:

22.5 J

Explanation:

It loses the difference in kinetic energy between the starting and ending speeds and that is (1/2)(M)(V1)^2 - (1/2)(M)(V2)^2 = (1/2)(M)((V1)^2 -(V2)^2) = (1/2)(0.2 kg)((25)^2 - (20)^2) = 22.5 Joules.

For 1000 seconds , a current of 0.1 A flows so as to transfer charge of 100C

Answer:

pretty sure its studying the atomic structure of a solid carbon dioxide. so c

Explanation:

Answer:

B. Studying the atomic structure of solid carbon dioxide

Explanation:

This is known as crystallography, the study of the arrangement of atoms in a solid, and it is a popular branch of solid-state physics.

Hope this helps :)

Answer:

Explanation:

This is very straightforward, except that we need the mass in kg and it's in g. So we have to convert first, using the fact that there are 1000g in 1 kg:

[tex]200g*\frac{1kg}{1000g}=.200kg[/tex] and now we're ready to solve your problem.

F = ma and

120 = .200a so

a = 6.0 × 10² (which is 600 m/s/s)

Answer:

1.4×10⁵ m/s

Explanation:

Applying,

K = mv²/2............. Equation 1

Where K = Energy of the satellite, m = mass of the satellite, v = speed of the satellite.

make v the subject of the equation

v = √(2K/m)............ Equation 2

From the question,

Given: K = 9.8×10⁹ J, m = 1000 g = 1 kg

Substitute these values into equation 2

v = √(2×9.8×10⁹/1)

v = √(1.96×10¹⁰)

v = 1.4×10⁵ m/s

Answer:

Rovers, unmanned space probes, modern instruments,

Explanation:

Answer:

eu não consigo entender essa situação o Fim dessa história só pode ter confusão dos iguais com cabeças diferentes a invés de amigas são concorrentes

The electric force between two charges is:

F = (9 x 10⁹) Q₁ Q₂ / D²

F is the force, in Newtons

Q₁ and Q₂ are the two charges, in Coulombs

D is the distance between them, in meters

For these two particles:

F = (9 x 10⁹) (0.35) (0.35) / (1)²

F = (9 x 0.35 x 0.35 x 10⁹) / (1)

F = 1.10 x 10⁹  Newtons

Thatsa lotta force . . . like 124 thousand tons !

The reason it's so big is because the charges in this question are so big ... 0.35 Coulombs each.  1 Coulomb is a huge amount of charge.

Each of the particles feels the same force, pushing it away from the other particle.  (The electric force between two charges is always the same in both directions, just like the gravitational force between two masses.)

Acc. to columb's law;

Clearly, from the question you have:

Now just put them up in the formula:

F = k × Q1Q2/r²

F = 9 × 10⁹ × 0.35 × 0.35/1 × 10-¹⁰

F = 9 × 10⁹ × 35 × 35/ 10-¹⁰ × 100 × 100

F = 9 × 10⁹ × 35 × 35/ 10-¹⁰ × 10⁴

F = 9 × 10⁹ × 35 × 35/ 10-⁶

F = 9 × 10⁹+⁶ × 1225

F = 11025 × 10¹⁵

Answer:

let one capacitor be x and other be y

[tex]in \: parallel \: connection : \\ \frac{x + y}{xy} = 10 \times {10}^{ - 6} - - - (a) \\ in \: series \: connection : \\ x + y = 2.4 \times {10}^{ - 6} - - - (b) \\ in \: (a) : \\ \frac{2.4 \times {10}^{ - 6} }{xy} = 10 \times {10}^{ - 6} \\ xy = 0.24 - - - (c) \\ from \: (b) : \\ y = (2.4 \times {10}^{ - 6} ) - x \\ \therefore \: in \: (c) : \\ x(2.4 \times {10}^{ - 6} - x) = 0.24 \\ 2.4 \times {10}^{ - 6} x - {x}^{2} = 0.24 \\ {x}^{2} - 2.4 \times {10}^{ - 6} x - 0.24 = 0 \\ x = 0.5 \\ 0.5y = 0.24 \\ y = 0.48 \\ { \boxed{ C _{1} = 0.5 \: farads}} \\ { \boxed{C _{2} = 0.48 \: farads}}[/tex]