It is called a negative nuetron/atom
        
                    
             
        
        
        
Answer:
stress tension tensile strength
Explanation:
The maximum stress which a material can withstand when it is pulled apart is its: stress tension tensile strength.
 
        
                    
             
        
        
        
Answer:
94
Explanation:
f = 2.57 x 10^13 Hz
E = 10 eV = 10 x 1.6 x 10^-19 J = 1.6 x 10^-18 J 
Energy of each photon = h f 
Where, h is Plank's constant
Energy of each photon = 6.63 x 10^-34 x 2.57 x 10^13 = 1.7 x 10^-20 J 
Number of photons = Total energy / energy of one photon 
N = (1.6 x 10^-18) / (1.7 x 10^-20) = 94.11 = 94
 
        
             
        
        
        
Answer:
All statement are correct. 
Explanation:
1. Electric field lines are the same thing as electric field vectors, electric field are mathematically vectors quantity. These vectors point in the direction in which a positive test charge would move. 
2.  Electric field line drawings allow you to determine the approximate direction of the electric field at a point in space. Yes it is correct tangent drawn at any point on these lines gives the direction of electric filed at that point. 
3. The number of electric field lines that start or end at a charged particle is proportional to the magnitude of charge on the particle, is a correct statement. 
4.The electric field is strongest where the electric field lines are close together, again a correct statement as relative closeness of field lines indicate a stronger strength of electric field. 
Hence we can say that all the statement are correct. 
 
        
             
        
        
        
<span>First of all, the maximum speed occurs when the object passes through the
 equilibrium position
The kinetic energy when the object has this max speed is
K= 1/2 * mass * (1.25 m/s)^2 
The potential energy in the spring when the speed is equal to zero
U= 1/2 * k * xmax^2 
The maximun force of the spring is 
mass*acceleration = k*xmax
m * 6.89 m/s2 = k * xmax 
xmax = 6.89* m / k 
0.5 * m * 1.56  = 0.5 * k * xmax^2 
</span>m * 1.56  =  k * (<span>6.89* m / k )^2 </span>
<span>
1.56 m = 47.47 m^2 / k 
m/k = 0.032862
period = 2 *pi*sqrt[m/k] 
= 2 pi </span><span>sqrt [ </span><span>0.032862] 
= 1.139  s 
 
A fourth of the period elapses between the instants of max acceleration and maximum speed
= 1/4* period 
= 1/4 * </span><span><span>1.139  s </span>
= 0.284s </span>