In June 21 are there more hours of daylight in San Francisco or the equator explain

550 g of water at 105°C is poured into an 855 g aluminum container with an initial temperature of 11°C. The specific heat of alu

nexus9112 [7]

Answer:

54.22 kJ

Explanation:

In this case, we need to calculate the heat. The expression to use is:

Q = m * C * ΔT

Now, with the specific heat of water (4186 J/ kg K), we can calculate the temperature in which this occurs.

So:

Q = 0.550 * 4186 * (105 - T)

Q = 2302.3 (105 - T)

Q = 241,741.5 - 2302.3T

Now with the Aluminium:

Q = 0.855 * 900 * (T - 11)

Q = 769.5T - 8464.5

Now, with both equations, we solve for the final temperature:

769.5T - 8464.5 = 241,741.5 - 2302.3T

(2302.3 + 769.5)T = 241,741.5 + 8464.5

3071.8T = 250,206

T = 81.45 K

This is the temperature which the change occurs. Now, let's determine the amount of heat from water to Al:

Q = 241,741.5 - 2302.3(81.45)

Q = 54,219.17 J or simply 54.22 kJ.

5 0

2 years ago

David is driving a steady 28.0 m/s when he passes Tina, who is sitting in her car at rest. Tina begins to accelerate at a steady

rodikova [14]

Answer:

Explanation:

Let t represent the time for Tina to catch David.

Hence, considering the equation of linear motion S = ut + 1/2at^2..... 1

For David u = 28.0 m/s where 'a' is set to nought

S = ut

S = 28t.......2

For Tina consider equation 1

Where acceleration = 2.90m/s^2 and u is set at nought

S = 1/2×2.90 m/s×t^2.......3

Equate 2 and 3

28t = 1.45t^2

Divide through by t

28 = 1.45t

t = 28/1.45

t = 19.31seconds

Now put the value of t into equation 3

S = 1/2×2.90 m/s×t^2.......3

= 1.45×20×20

= 580m

Tina must have driven 580meters before passing David

Considering the equation of linear motion : V^2 = U^2+2as

Where u is set at nought

V^2 = 2as

V^2 = 2×2.9×580

V^2 = 3364

V = √3364

V = 58m/s

Her speed will be 58m/s

7 0

2 years ago

Think of three questions that will help you clarify your understanding of how of the factors that have contributed to the rise i

fenix001 [56]

Answer:

the glucose in air will solidify and it will stop the process.

it will cause hot air

6 0

2 years ago

Read 2 more answers

A hydraulic lift has pistons with diameter 28cm and 70cm, respectively. If a force of 500 N is exerted at the input piston. What

Crazy boy [7]

Answer:

3125 N

Explanation:

diameter /2 =radius

so r1 =14cm , r2 =35cm

f1/A1 =f2/A2.

f2 = f1 × A2 / A1

=500×1225 pi cm² / 96 pi cm²

f2 =3125N

4 0

3 years ago

It took a crew 9 h 36 min to row 8 km upstream and back again. If the rate of flow of the stream was 2 km/h, what was the rowing

babunello [35]

Answer:

3 km/h

Explanation:

Let's call the rowing speed in still water x, in km/h.

Rowing speed in upstream is: x - 2 km/h

Rowing speed in downstream is: x + 2 km/h

It took a crew 9 h 36 min ( = 9 3/5 = 48/5) to row 8 km upstream and back again. Therefore:

8/(x - 2) + 8/(x + 2) = 48/5 (notice that: time = distance/speed)

Multiplying by x² - 2², which is equivalent to (x-2)*(x+2)

8*(x+2) + 8*(x-2) = (48/5)*(x² - 4)

Dividing by 8

(x+2) + (x-2) = (6/5)*(x² - 4)

2*x = (6/5)*x² - 24/5

0 = (6/5)*x² - 2*x - 24/5

Using quadratic formula

$x = \frac{2 \pm \sqrt{(-2)^2 - 4(6/5)(-24/5)}}{2(6/5)}$

$x = \frac{2 \pm 5.2}{2.4}$

$x_1 = \frac{2 + 5.2}{2.4}$

$x_1 = 3$

$x_2 = \frac{2 - 5.2}{2.4}$

$x_2 = -1\; 1/3$

A negative result has no sense, therefore the rowing speed in still water was 3 km/h

7 0

3 years ago