Which of the following occurs when a catalyst is used in a chemical reaction?
A. the catalyst speeds up the rate of the chemical reaction
B. the catalyst always brings the reactants close together
C. the catalyst is permanently changed by the reaction
D. the catalyst increases the activation energy needed for the reaction to take place

Answer:

i'll answer your question but follow me first

Answer:

By the help of magnetic field of the earth

Explanation:

Compasses, also known as magnetic compass, help us primarily in navigating and determine position on the globe. The planet Earth has its own magnetosphere or magnetic field that is close with that of a magnetic poles, and this is how compass works. The compass needle aims north and south as it happens to coincide with the Magnetosphere or magnetic field.

Answer:

Newton's second law of motion?

3,970.8

Explanation:

v=661.8×6

3,970.8

Answer:

One of the more important properties of sound is that its speed is nearly independent of frequency. ... Therefore, the relationship between f and λ is inverse: The higher the frequency, the shorter the wavelength of a sound wave. The speed of sound can change when sound travels from one medium to another.

Answer:D.Refractive Indez

Explanation:

It is usually expressed the other way: the ratio of the speed of light in a vacuum to the speed of light in a medium. In that case, it is called the "index of refraction".

You're going for "refractive index", but you've got the ratio flipped over.

Answer:

They do that by converting rotating mechanical energy into electrical power. Portable generators use an engine—typically running on gasoline, diesel, or propane, to turn an alternator which produces alternating electrical current or AC.

Answer:

By pointing one's right thumb along the direction of the current, the direction of the magnetic field can by found by curving one's fingers around the wire. The strength of the magnetic field depends on the current I in the wire and r, the distance from the wire.

Answer:

germ cleaning

and getting up cooking grease

Explanation:

Answer:

120 kgm/s

Explanation:

Force= mass× acceleration

= 60kg × 2.0m/s

= 120 kgm/s

Answer:

PRESSURE is a force exerted by the substance per unit area on another substance.

The key difference between water pressure and air pressure is that one is made up of water and the other is made up of air. Both air pressure and water pressure are based on and follow the same physical principals.

Explanation:

Answer:

Explanation:

Quantum theory has taught us that virtually everything to do with the nature of matter in the universe is a random process. The decay of atomic nuclei is something that makes that randomness "visible" with appropriate instrumentation. As such, the rate of decay will vary over the "short" term. Consequently, it is not surprising to see a variation of a few counts in an activity measurement over a period of a few minutes.

__

Safety with respect to radioactive materials involves staying as far away from them as possible. The use of long tongs for handling would be appropriate.

Answer:

↔ for safety precautions the scientist should used this upon working with radioactive materials in a laboratory.

Answer:

Velocidad final, V = 8 m/s

Explanation:

Dados los siguientes datos;

Velocidad inicial, u = 4 m/s

Aceleración, a = 2 m/s²

Tiempo, t = 2 segundos

Para encontrar la velocidad final (v), usaríamos la primera ecuación de movimiento;

V = u + at

Sustituyendo en la fórmula, tenemos;

V = 4 + 2*2

V = 4 + 4

Velocidad final, V = 8 m/s

Answer:

I think it is protection

Answer:

I think it might be PROTECTION but i not sure for a fact

Sorry if i get it wrong ;]

Explanation:

Answer:

The answer is "[tex]0.13562748[/tex]"

Explanation:

Please find the complete question in the attached file.

Using formula:

[tex]\bold{U_s=\frac{v^2}{rg}}[/tex]

Given:

[tex]r=1.60 \times 10^2 \ m\\\\g=9.8\\\\v= 52.5\ \frac{km}{hr}= 14.583\ \frac{m}{s}[/tex]

put the value into the above-given formula:

[tex]U_s= \frac{14.583^2}{160 \times 9.8}[/tex]

    [tex]= \frac{212.663889}{1568}\\\\=0.13562748[/tex]

Answer:

the capacity to do work is called energy

Answer:

0.19 and 0.45

Explanation:

edge

The first and second velocities of the car are [tex]0.25/t_1[/tex] and [tex]0.50/t_2[/tex]respectively.

The velocity of an object is defined as the product of the distance travelled in a given direction and the time required to travel that distance. The velocity is expressed mathematically as,

v = d/t

Here, d represents the travelled distance.

And t is the typical amount of time needed to go the distance.

Given,

The value of the first distance is, d1 = 0.25 m.

The value of the second distance is, d2 = 0.50 m.

Then the first velocity of the car at 0.25 m is,

[tex]v_1 = d_1/t_1\\v_1 = 0.25 / t_1[/tex]

Thus,[tex]t_1[/tex] denotes the first distance's typical time.

The second velocity of the car with three washers at the 0. 50 m mark is

[tex]v_2 = d_2/t_2\\v_2 = 0.50 /t_2[/tex]

Here, [tex]t_2[/tex] stands for the second distance's typical time.

Thus, the first and second velocities of the car are [tex]0.25/t_1[/tex] and [tex]0.50/t_2[/tex]respectively.

Learn more about Velocity, here:

brainly.com/question/25796948

#SPJ2

Answer:

C. Greenhouse Effect

Explanation:

The greenhouse effect is caused by heat trapping pollution in the atmosphere.

Answer:

Presión = 11111,11 N/m

Explanation:

Dados los siguientes datos;

Diámetro = 1,5 cm a metros = 1,5 / 100 = 0,015 m

Fuerza = 2N

Para encontrar la presión;

En primer lugar, determinaríamos el área del círculo usando la fórmula;

Área del círculo = πr²

Radio = diámetro/2 = 0.015/2 = 0.0075 m

Área de la jeringa = 3.142 * 0.0075²

Área de la jeringa = 3.142 * 0.00005625

Área de la jeringa = 0.00018 metros

Ahora, podemos encontrar la presión usando la fórmula;

Presión = fuerza/área

Presión = 2/0.00018

Presión = 11111,11 N/m

Answer: Wave a the first answer is right

Brainliest.

Explanation:

Answer:

25

Explanation:

I just did this

exothermic

Explanation:

negative means it's losing energy

Answer:

5 seconds

Explanation:

Answer:

do not require a medium

Explanation:

Light waves can be regarded as electromagnetic waves and it transverse in nature, no medium material is required to pass through. Light wave can travel through vacuum and it's ray can travel in straight lines even from point source. Light convey energy in perpendicular direction to electric field as well as magnetic field.

Answer:

The (vertical) speed of the driver as he strikes the water is approximately 18.22 m/s

Explanation:

From the parameters given in the question, we have;

The time after which the driver strikes the water after he drives off a platform, t = 1.857 s

Let 'v' represent the vertical speed of the driver

We can find the vertical speed of the vehicle as it strikes the water as follows;

v = u + g·t

Where;

v = The final vertical velocity of the driver

u = The initial vertical speed of the driver = 0 m/s

g = The acceleration due to gravity ≈ 9.81 m/s²

t = The time of motion = 1.857 seconds

Therefore, we have;

v = 0 + 9.81 m/s² × 1.857 s = 18.21717 m/s

Therefore;

The vertical speed of the driver as he strikes the water, v ≈ 18.22 m/s

Answer:

the correct answer is 1. radiation