Question 10 of 10

Why is it recommended that windows face north in Alice Springs, Australia for passive solar heating?

ladessa [460]

The Passive solar heating uses free free heating direct from the sun to reduce the estimated forty percent of energy consumed in the average australian home for space heating and cooling. many heating and cooling design objectives overlap but different emphasis is required depends on your climate need.

4 0

3 years ago

A runner is jogging in a straight line at a

Fiesta28 [93]

Answer:

Total distance traveled by bird is 10.5 km.

Explanation:

Given that,

Velocity of runner= 8.4 km/hr

Distance = 6.3 km

Velocity of bird = 42 km/hr

Suppose, How far does the bird travel?

We need to calculate the time of bird

Using formula of time

$t=\dfrac{d}{v_{b}}$

Put the value into the formula

$t=\dfrac{6.3}{42}$

$t=0.15\ hr$

We need to calculate the distance runner travels during time period

Using formula of distance

$d=v_{r}\times t$

$d=8.4\times0.15$

$d=1.26\ km$

We need to calculate the distance of runner to FL

Using distance

$d'=6.3-1.26$

$d'=5.04\ km$

We need to calculate the net closing speed between runner and bird

Using speed

$v'=v_{r}+v_{b}$

$v'=8.4+42$

$v'=50.4\ km/hr$

We need to calculate the time for runner and bird to meet

Using formula of time

$t=\dfrac{d}{v'}$

Put the value into the formula

$t=\dfrac{5.04}{50.4}$

$t=0.1\ hr$

We need to calculate the distance covered by runner

Using formula of distance

$d=vt$

Put the value into the formula

$d=8.4\times0.1$

$d=0.84\ km$

We need to calculate the distance covered by bird to runner

Using formula of distance

$d=vt$

Put the value into the formula

$d=42\times0.1$

$d=4.2\ km$

We need to calculate the total distance

Using distance

$D=6.3+4.2$

$D=10.5\ km$

Hence, Total distance traveled by bird is 10.5 km.

4 0

3 years ago

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arr

Nitella [24]

Answer:

1. Part A: 648N
2. Part B: 324J
3. Part C: 1,296N

Explanation:

1. Part A:

The magnitude of the force is calculated using the Hook's law:

$|F|=k\Delta x$

You know $\Delta x=0.250m$ but you do not have $k$ .

You can calculate it using the equation for the work-energy for a spring.

The work done to compress the springs a distance $\Delta x$ is:

$Work=\Delta PE=(1/2)k(\Delta x)^2$

Where $\Delta PE$ is the change in the elastic potential energy of the "spring".

Here you have two springs, but you can work as if they were one spring.

You know the work (81.0J) and the length the "spring" was compressed (0.250m). Thus, just substitute and solve for k:

$81.0J=(1/2)k(0.250m)^2\\\\k=2,592N/m$

In reallity, the constant of each spring is half of that, but it is not relevant for the calculations and you are safe by assuming that it is just one spring with that constant.

Now calculate the magnitude of the force:

$|F|=k\Delta x=2,592N/m\times 0.250m=648N$

2. Part B. How much additional work must you do to move the platform a distance 0.250 m farther?

The additional work will be the extra elastic potential energy that the springs earn.

You already know the elastic potential energy when Δx = 0.250m; now you must calculate the elastic potential energy when Δx = 0.250m + 0.250m = 0.500m.

$\Delta E=(1/2)2,592n/m\times(0.500m)^2=324J$

Therefore, you must do 324J of additional work to move the plattarform a distance 0.250 m farther.

3. Part C

What maximum force must you apply to move the platform to the position in Part B?

The maximum force is when the springs are compressed the maximum and that is 0.500m

Therefore, use Hook's law again, but now the compression length is Δx = 0.500m

$|F|=k\Delta x=2,592N/m\times 0.500m =1,296N$

8 0

3 years ago

Night and day have approximately equal length at what time or times of the year?

Thepotemich [5.8K]

There are two every year – in September and March – when the Sun shines directly on the Equator and the length of day and night is nearly equal.

4 0

3 years ago

Most of the energy used by light on earth comes from

egoroff_w [7]

The sun, that's our main source. Without it the world can die

3 0

3 years ago