Answer:
Alfred Wegener proposed the idea that earths lithospher is divided into tectonic plates.The theory was only accepted after he died.
 
        
             
        
        
        
Physical change 1 is the answer
        
                    
             
        
        
        
In order to answer these questions, we need to know the charges on 
the electron and proton, and then we need to know the electron's mass.  
I'm beginning to get the creepy feeling that, in return for the generous 
5 points, you also want me to go and look these up so I can use them 
in calculations ... go and collect my own straw to make the bricks with, 
as it were.  
Ok, Rameses:
Elementary charge . . . . .  1.6 x 10⁻¹⁹  coulomb
                                        negative on the electron
                                        plussitive on the proton
Electron rest-mass . . . . .  9.11 x 10⁻³¹  kg
a).  The force between two charges is
      F  =  (9 x 10⁹) Q₁ Q₂ / R²
          =  (9 x 10⁹ m/farad) (-1.6 x 10⁻¹⁹C) (1.6 x 10⁻¹⁹C) / (5.35 x 10⁻¹¹m)² 
          =     ( -2.304 x 10⁻²⁸) / (5.35 x 10⁻¹¹)²
          =          8.05 x 10⁻⁸  Newton .
b).  Centripetal acceleration  =  
                                               v² / r  .
                  A  =  (2.03 x 10⁶)² / (5.35 x 10⁻¹¹)
                     =      7.7 x 10²²  m/s² .
That's an enormous acceleration ... about  7.85 x 10²¹  G's !
More than enough to cause the poor electron to lose its lunch.
It would be so easy to check this work of mine ...
First I calculated the force, then I calculated the centripetal acceleration.
I didn't use either answer to find the other one, and I didn't use  "  F = MA "
either.
I could just take the ' F ' that I found, and the 'A' that I found, and the
electron mass that I looked up, and mash the numbers together to see
whether  F = M A .
I'm going to leave that step for you.   Good luck !
        
             
        
        
        
Answer:
1.171
Explanation:
if n₁sinΘ₁=n₂sinΘ₂, then n₂=n₁sinΘ₁ / sinΘ₂;

 
        
             
        
        
        
The  force required to pull one of the microscope sliding at a constant speed of 0.28 m/s relative to the other is zero.
<h3>
Force required to pull one end at a constant speed</h3>
The force required to pull one of the microscope sliding at a constant speed of 0.28 m/s relative to the other is determined by applying Newton's second law of motion as shown below;
F = ma
where;
- m is mass
- a is acceleration
At a constant speed, the acceleration of the object will be zero.
F = m x 0
F = 0
Thus, the  force required to pull one of the microscope sliding at a constant speed of 0.28 m/s relative to the other is zero.
Learn more about constant speed here: brainly.com/question/2681210