no, it not useless. we still learn Bohr's model in HS n dats almost 200 yr old! while there may be new models, previous one is good for explaining the basics. it is also useful to learn previous model n see how our understanding improves over time.
Answer:
15.75 m
Explanation:
First, let's look at the top brick by itself. In order for it not to tip over the bottom brick, its center of gravity must be right at the edge of the bottom brick. So the edge of the top brick must be 10.5 m from the edge of the bottom brick.
Now let's look at both bricks as a combined mass. We know the total length of this combined brick is 10.5 m + 21 m = 31.5 m. And we know that for it to not tip over the edge of the surface, its center of gravity must be at the edge. So the edge of the combined brick must be 31.5 m / 2 = 15.75 m from the edge of the surface.
The correct answers are <span>starting friction and </span>static friction
Friction slows down all forces, but starting friction slows down or stops completely the start of motion.
Answer:
Weight of the woman in Newton

Mass of the woman in slug

Mass of the woman in kg

My weight in Newton

Explanation:
From the question we are told that
The weight of the woman in pounds is 
Converting to Newton
1 N = 0.22472 lb
x N = 157
=> 
=> 
Obtaining the mass in slug

Here 
So


Obtaining the mass in kilogram

Here 
So


Generally weight is mathematically represented as

Given that my mass is 80 kg then my weight is


17. a sea breeze is a breeze blowing towards the land
18. a land breeze is a breeze blowing towards the sea