A skier is skiing down a slope on a mountain. Is mechanical energy conserved?

how is momentum conserved when a cue ball moving with a velocity of 1.5 m/s strikes another billiard ball white playing pool? Sh

mote1985 [20]

according to conservation of momentum , total sum of momentum of the objects taking part in a collision is same before and after the collision.

Total momentum before collision = Total momentum after the collision

when a cue ball moving at velocity 1.5 m/s hits a billiard ball , transfer of momentum takes place between the balls such that total sum of momentum of cue ball and billiard ball remain same before and after the collision.

hence we say that the momentum is conserved.

8 0

3 years ago

An ocean thermal energy conversion system is being proposed for electric power generation. Such a system is based on the standar

defon

Answer:

Explanation:

Dear Student, this question is incomplete, and to attempt this question, we have attached the complete copy of the question in the image below. Please, Kindly refer to it when going through the solution to the question.

To objective is to find the:

(i) required heat exchanger area.

(ii) flow rate to be maintained in the evaporator.

Given that:

water temperature = 300 K

At a reasonable depth, the water is cold and its temperature = 280 K

The power output W = 2 MW

Efficiency $\zeta$ = 3%

where;

$\zeta = \dfrac{W_{out}}{Q_{supplied }}$

$Q_{supplied } = \dfrac{2}{0.03} \ MW$

$Q_{supplied } = 66.66 \ MW$

However, from the evaporator, the heat transfer Q can be determined by using the formula:

Q = UA(L MTD)

where;

$LMTD = \dfrac{\Delta T_1 - \Delta T_2}{In (\dfrac{\Delta T_1}{\Delta T_2} )}$

Also;

$\Delta T_1 = T_{h_{in}}- T_{c_{out}} \\ \\ \Delta T_1 = 300 -290 \\ \\ \Delta T_1 = 10 \ K$

$\Delta T_2 = T_{h_{in}}- T_{c_{out}} \\ \\ \Delta T_2 = 292 -290 \\ \\ \Delta T_2 = 2\ K$

$LMTD = \dfrac{10 -2}{In (\dfrac{10}{2} )}$

$LMTD = \dfrac{8}{In (5)}$

LMTD = 4.97

Thus, the required heat exchanger area A is calculated by using the formula:

$Q_H = UA (LMTD)$

where;

U = overall heat coefficient given as 1200 W/m².K

$66.667 \times 10^6 = 1200 \times A \times 4.97 \\ \\ A= \dfrac{66.667 \times 10^6}{1200 \times 4.97} \\ \\ \mathbf{A = 11178.236 \ m^2}$

The mass flow rate:

$Q_{H} = mC_p(T_{in} -T_{out} ) \\ \\ 66.667 \times 10^6= m \times 4.18 (300 -292) \\ \\ m = \dfrac{ 66.667 \times 10^6}{4.18 \times 8} \\ \\ \mathbf{m = 1993630.383 \ kg/s}$

3 0

3 years ago

Difference between uniform motion and non uniform motion <br>

photoshop1234 [79]

Answer:

Uniform motion is a type of motion that is characterized as the motion of an object wherein the object moves in a straight line and its velocity remains unchanged along that line, regardless of the duration of time, as it occupies equal distances at equal time interval and Non-uniform motion is described as the motion of an object wherein the object moves at different speeds and does not cover the same distance at equal time intervals, regardless of the duration of the time interval.

5 0

3 years ago

Read 2 more answers

zybooks One AA battery in a flashlight stores 9400 J. The three LED flashlight bulbs consume 0.5 W. How many hours will the flas

Rom4ik [11]

Answer:

The time for which the flashlight last is 5.23 hours.

Explanation:

Given that,

One AA battery in a flashlight stores 9400 J, E = 9400 J

Power consumed by the LED flashlight bulbs, P = 0.5 W

We need to find the time for which the flashlight last. The power of a device is given by the energy stored per unit time as :

$P=\dfrac{E}{t}$

$t=\dfrac{E}{P}$

$t=\dfrac{9400\ J}{0.5\ W}$

t = 18800 seconds

or

Since, 1 hour = 3600 seconds

t = 5.23 hours

So, the time for which the flashlight last is 5.23 hours. Hence, this is the required solution.

7 0

3 years ago

Calculating Displacement from the Area under a Curve Try Use the graph to answer the question What is the total displacement of

Agata [3.3K]

Answer:

175 m

Explanation:

In a velocity vs time graph, displacement is the area under the curve.

We can calculate this as area of a trapezoid:

A = ½ (10 m/s + 60 m/s) (5 s)

A = 175 m

Or, we can split the area into a rectangle and a triangle.

A = (10 m/s) (5 s) + ½ (60 m/s − 10 m/s) (5 s)

A = 175 m

8 0

3 years ago