Answer:
the tension of the rope is 34.95 N
Explanation:
Given;
length of the rope, L = 3 m
mass of the rope, m = 0.105 kg
frequency of the wave, f = 40 Hz
wavelength of the wave, λ = 0.79 m 
Let the tension of the rope = T
The speed of the wave is given as;

Therefore, the tension of the rope is 34.95 N
 
        
             
        
        
        
Answer:
0.47 N
Explanation:
Here we have a ball in motion along a circular track.
For an object in circular motion, there is a force that "pulls" the object towards the centre of the circle, and this force is responsible for keeping the object in circular motion.
This force is called centripetal force, and its magnitude is given by:

where
m is the mass of the object
 is the angular velocity
 is the angular velocity 
r is the radius of the circle
For the ball in this problem we have:
m = 40 g = 0.04 kg is the mass of the ball
 is the angular velocity
 is the angular velocity
r = 30 cm = 0.30 m is the radius of the circle
Substituting, we find the force:

 
        
             
        
        
        
Answer:
Explanation:
Let m be mass of each sphere and θ be angle, string makes with vertex in equilibrium. 
Let T be tension in the hanging string 
T cosθ = mg ( for balancing in vertical direction )
for balancing in horizontal direction
Tsinθ = F ( F is force of repulsion between two charges sphere)
Dividing the two equations 
Tanθ = F / mg 
tan17 = F / (7.1 x 10⁻³ x 9.8)
F = 21.27 x 10⁻³ N 
if q be charge on each sphere , force of repulsion between the two
F = k q x q / r² ( r is distance between two sphere , r = 2 x .7 x sin17  = .41 m )
 21.27 x 10⁻³  = (9 X 10⁹ x q²) / .41² 
q² = .3973 x 10⁻¹²
q = .63 x 10⁻⁶ C 
no of electrons required  = q / charge on a single electron 
= .63 x 10⁻⁶ / 1.6 x 10⁻¹⁹
= .39375 x 10¹³
3.9375 x 10¹² . 
 
        
             
        
        
        
answer  for number nine is C
Convergent boundaries: where two plates are colliding. Subduction zones occur when one or both of the tectonic plates are composed of oceanic crust. 
Divergent boundaries – where two plates are moving apart. ...
Transform boundaries – where plates slide passed each other.
answer for number eight is d.
hope this help you
 
        
                    
             
        
        
        
When I went through with the math, the answer I came upon was: 
<span>6.67 X 10^14 </span>
<span>Here is how I did it: First of all we need to know the equation. </span>
<span>c=nu X lamda </span>
<span>(speed of light) = (frequency)(wavelength) </span>
<span>(3.0 X 10^8 m/s) = (frequency)(450nm) </span>
<span>We want the answer in meters so we need to convert 450nm to meters. </span>
<span>450nm= 4.5 X 10^ -7 m </span>
<span>(3.0 X 10^8 m/s) = (frequency)(4.5 X 10^ -7 m) </span>
<span>Divide the speed of light by the wavelength. </span>
<span>(3.0 X 10^8m/s) / (4.5 X 10^ -7m) =6.67 X 10^ 14 per second or s- </span>
<span>Answer: 6.67 X 10^14 s- hope this helps</span>