Answer:
1. 
2. 
Explanation:
1.
Given:
- height of the window pane,

- width of the window pane,

- thickness of the pane,

- thermal conductivity of the glass pane,

- temperature of the inner surface,

- temperature of the outer surface,

<u>According to the Fourier's law the rate of heat transfer is given as:</u>

here:
A = area through which the heat transfer occurs = 
dT = temperature difference across the thickness of the surface = 
dx = t = thickness normal to the surface = 


2.
- air spacing between two glass panes,

- area of each glass pane,

- thermal conductivity of air,

- temperature difference between the surfaces,

<u>Assuming layered transfer of heat through the air and the air between the glasses is always still:</u>



Answer:
Here are 2 sense i cant find 4
Explanation:
Levers are used to multiply force, In other words, using a lever gives you greater force or power than the effort you put in.
In a lever, if the distance from the effort to the fulcrum is longer than the distance from the load to the fulcrum, this gives a greater mechanical advantage.
Answer:

Explanation:
In electrical terms, is the ratio of time in which a load or circuit is ON compared to the time in which the load or circuit is OFF.
The duty cycle or power cycle, is expressed as a percentage of the activation time. For example, a 70% duty cycle is a signal that 70% of the time is activated and the other 30% disabled. Its equation can be expressed as:

Where:



Here is a picture that will help you understand these concepts.
Structure Of The Atom: Our current model of the atom can be broken down into three constituents parts – protons, neutron, and electrons. Each of these parts has an associated charge, with protons carrying a positive charge, electrons having a negative charge, and neutrons possessing no net charge.