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2 years ago

5

Often times we think about insulation, we think about keeping cold items cold, such as drinks in an ice chest or the cool temper

ature in your home. But insulation also keeps things high! The same thermos that keeps your water cold keep your hot chocolate worm. How was that possible?

1 answer:

Burka [1]2 years ago

4 0

Answer:

So, insulation essentially works by creating a sort of barrier between the hot and the cold object. This barrier helps to reduce heat transfer by either reflecting the thermal radiation or by decreasing thermal conduction and convection from one object to the other.

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What does the Pauli exclusion principle state? . . A.Electrons will be added to an atom at the lowest possible level or sublevel

BARSIC [14]

The Pauli exclusion principle state that : D. Two electrons occupy the same orbital only if they have opposite spins

This happen because he stated that in an atom or molecule, two electrons CANNOT have same four electronic quantum numbers

hope this helps

5 0

3 years ago

Two 51 g blocks are held 30 cm above a table. As shown in the figure, one of them is just touching a 30-long spring. The blocks

vivado [14]

The concept of this question can be well understood by listing out the parameters given.

The mass of the block = 51 g = 51 × 10⁻³ kg
The distance of the block from the table = 30 cm
Length of the spring = 30 cm

The purpose is to determine the spring constant.

Let us assume that the two blocks are Block A and Block B.

At point A on block A, the initial velocity on the block is zero

i.e. u = 0

We want to determine the time it requires for Block A to reach the table. The can be achieved by using the second equation of motion which can be expressed by using the formula.

$\mathsf{S = ut + \dfrac{1}{2}gt^2}$

From the above formula,

The distance (S) = 30 cm; we need to convert the unit to meter (m).

Since 1 cm = 0.01 m
Then, 30cm = 0.3 m

The acceleration (g) due to gravity = 9.8 m/s²

∴

inputting the values into the equation above, we have;

$\mathsf{0.3 = (0)t + \dfrac{1}{2}*(9.80)*(t^2)}$

$\mathsf{0.3 = \dfrac{1}{2}*(9.80)*(t^2)}$

$\mathsf{0.3 =4.9*(t^2)}$

By dividing both sides by 4.9, we have:

$\mathsf{t^2 = \dfrac{0.3}{4.9}}$

$\mathsf{t^2 = 0.0612}$

$\mathsf{t = \sqrt{0.0612}}$

$\mathsf{t =0.247 \ seconds}$

However, block B comes to an instantaneous rest on point C. This is achieved by the dropping of the block on the spring. During this process, the spring is compressed and it bounces back to oscillate in that manner. The required time needed to get to this point C is half the period, this will eventually lead to the bouncing back of the block with another half of the period, thereby completing a movement of one period.

By applying the equation of the time period of a simple harmonic motion.

$\mathsf{T = 2 \pi \sqrt{\dfrac{m}{k}}}$

where the relation between time (t) and period (T) is:

$\mathsf{t = \dfrac{T}{2}}$

T = 2t

T = 2(0.247)

T = 0.494 seconds

$\mathsf{T = 2 \pi \sqrt{\dfrac{m}{k}}}$

By making the spring constant k the subject of the formula:

$\mathsf{\dfrac{T}{2 \pi } = \sqrt{ \dfrac{m}{k}}}$

$\Big(\dfrac{T}{2 \pi }\Big)^2 = { \dfrac{m}{k}$

$\dfrac{T^2}{(2 \pi)^2 }= { \dfrac{m}{k}$

$\mathsf{ T^2 *k = 2 \pi^2*m} \\ \\ \mathsf{ k = \dfrac{2 \pi^2*m}{T^2}}$

$\mathsf{ k =\Big( \dfrac{(2 \pi)^2*(51 \times 10^{-3})}{(0.494)^2} \Big) N/m}$

$\mathbf{ k =8.25 \ N/m}$

Therefore, we conclude that the spring constant as a result of instantaneous rest caused by the compression of the spring is 8.25 N/m.

Learn more about simple harmonic motion here:

brainly.com/question/17315536?referrer=searchResults

6 0

3 years ago

In a few sentences, compare and contrast pressurized water reactors and boiling water reactors.

kondaur [170]

For pressurized water reactors the coolant is not permitted to boil in the core of the PRW, however the coolant in boiling water reactors is permitted to do so in the core of BWR. Pressurized water reactors have an indirect cycle. Whereas, the boiling water reactors go through a direct cycle. Both are light water reactors.

6 0

3 years ago

Read 2 more answers

What is the main reason for using a data table for collecting data?

Luba_88 [7]

Answer:

to make calculation more easy to get

Explanation:

if you are using chart or calculate Thermodynamic problems you will not never solve this problem with out using data table for thermodynamic

7 0

3 years ago

In just 0.30 s , you compress a spring (spring constant 5000 n/m ), which is initially at its equilibrium length, by 4.0 cm. par

Ierofanga [76]

The average power output is the ratio between the work done to compress the spring, W, and the time taken, t:
$P= \frac{W}{t}$ (1)

The work done is equal to the elastic energy stored by the compressed spring:
$W=U= \frac{1}{2}kx^2$
where $k=5000 N/m$ is the spring constant and $x=4.0 cm=0.04 m$ is the compression of the spring. If we substitute the numbers, we find:
$W= \frac{1}{2}(5000 N/m)(0.04 m)^2=4 J$

And now we can use eq.(1) to calculate the average power output:
$P= \frac{W}{t}= \frac{4 J}{0.30 s} =13.3 W$

7 0

3 years ago