Which process requires the addition of energy to water?

A person standing at the edge of a seaside cliff kicks a stone horizontally over the edge with a speed of 18 m/s. The cliff is 5

Fed [463]

Answer:

it would take 3.26 seg for the stone to fall to the water

Explanation:

If we ignore air friction then:

h=h₀ + v₀*t -1/2*g*t²

where

h= coordinates of the stone in the y axis ( height of the stone relative to the surface of the water )

h₀ = initial coordinates of the stone ( height of the cliff relative to the surface of the water = 52 m )

v₀ = initial <u>vertical </u>velocity = 0 ( since the ball is kicked horizontally , has only initial horizontal velocity , and has 0 vertical velocity )

t = time to reach a height h

g = gravity = 9.8 m/s²

since v₀ =0

h= h₀ - 1/2*g*t²

h₀ - h = 1/2*g*t²

t= √[2(h₀ - h)/g]

when the stone hits the ground h=0 ( height=0) , then replacing values

t=√[2(h₀ - h)/g]=√[2(52 m- 0 m )/(9.8m/s²)] = 3.26 seg

t= 3.26 seg

it would take 3.26 seg for the stone to fall to the water

7 0

4 years ago

El muelle de un dinamómetro se alarga 6cm cuando aplicamos sobre él una fuerza de 10 N. Calcula el alargamiento del muelle al ap

Crank

Answer:

x = 12cm

Explanation:

First, with the values given for the force and the displacement, you calculate the spring-constant of the dynamometer by using the following equation (primero, con los valores dados de la fuerza y el desplazamiento, calculas la constante del resorte aplicando la siguiente formula):

$F=kx$

F: force (fuerza) = 10N

k: spring constant (constante del resorte)

x: displacement of the spring (desplazamiento del resorte) = 6cm

by using these values you calculate k (usando estos valores calculas k):

$k=\frac{F}{x}=\frac{10N}{6cm}=1.66\frac{N}{cm}$

With this value you calculate the displacement for a force of 20N (con este valor de k calculas el desplazamiento del resorte para una fuerza de 20N):

$x=\frac{F}{k}=\frac{20}{1.66N/cm}=12cm$

hence, the displacement is 12cm

6 0

4 years ago

A squirrel jumps into the air with a velocity of 4 m/s at an angel of 50 degrees. What is the maximum height reached by the squi

Debora [2.8K]

Answer:

Explanation:

Assuming the squirrel is jumping off the ground, here's what we know but don't really know...

v₀ = 4.0 at 50.0°

So that's not really the velocity we are looking for. We are dealing with a max height problem, which is a y-dimension thing. Therefore, we need the squirrel's upward velocity, which is NOT 4.0 m/s. We find it in the following way:

$v_{0y}=4.0sin(50.0)$ which gives us that the upward velocity is

v₀ = 3.1 m/s

Moving on here's what we also know:

a = -9.8 m/s/s and

v = 0

Remember that at the very top of the parabolic path, the final velocity is 0. In order to find the max height of the squirrel, we need to know how long it took him to get there. We are using 2 of our 3 one-dimensional equations in this problem. To find time:

v = v₀ + at and filling in:

0 = 3.1 - 9.8t and

-3.1 = -9.8t so

t = .32 seconds.

Now that we know how long it took him to get to the max height, we use that in our next one-dimensional equation:

Δx = $v_0t+\frac{1}{2}at^2$ and filling in:

Δx = $3.1(.32)+\frac{1}{2}(-9.8)(.32)^2$ and using the rules for adding and subtracting sig fig's correctly, we can begin to simplify this:

Δx = .99 - .50 so

Δx = .49 meters

7 0

3 years ago

To lower the voltage from a "120 V" outlet, what is used (first, at least) in most situations

nasty-shy [4]

Answer:

B. Transformer

Explanation:

A transformer is a device that is used to either raise or lower voltages and currents in an electrical circuit. In modern electrical distribution systems, transformers are used to boost voltage levels so as to decrease line losses during transmission. It basically trades voltage for current in a circuit, while not affecting the total electrical power. This means it takes high-voltage electricity with a small current and changes it into low-voltage electricity with a large current, or vice versa.

4 0

3 years ago

The old rubber boot has two leaks. The top of the boot is 0.3 m higher than the leaks. What is the velocity of the water coming

Otrada [13]

Answer:

Leak 1 = 3.43 m/s

Leak 2 = 2.42 m/s

Explanation:

Given that the top of the boot is 0.3 m higher than the leaks.

Let height H = 0.3m and the acceleration due to gravity g = 9.8 m/s^2

From the figure, the angle of the leak 1 will be approximately equal to 45 degrees. While the leak two can be at 90 degrees.

Using the third equation of motion under gravity, we can calculate the velocity of leak 1 and 2

Find the attached files for the solution and figure

7 0

3 years ago