Answer:
P = 5.22 Kg.m/s
Explanation:
given,
mass of the projectile = 1.8 Kg
speed of the target = 4.8 m/s
angle of deflection = 60°
Speed after collision = 2.9 m/s
magnitude of momentum after collision = ?
initial momentum of the body = m x v 
                                                   = 1.8 x 4.8 = 8.64 kg.m/s
final momentum after collision 
 momentum along x-direction
P_x = m v cos θ
P_x = 1.8 x 2.9 x  cos 60°
P_x = 2.61 kg.m/s
momentum along y-direction
P_y = m v sin θ
P_y = 1.8 x 2.9 x  sin 60°
P_y = 4.52 kg.m/s
net momentum of the body


  P = 5.22 Kg.m/s
momentum magnitude after collision is equal to P = 5.22 Kg.m/s
 
        
             
        
        
        
You're answer is B. P waves are more dynamic and have a great autonomy to be able generate a earthquake.
        
             
        
        
        
Answer:Same magnitude
Explanation:
When ball is dropped from shoulder height h then velocity at the bottom is given by 

if it makes elastic collision then it will acquire the same velocity and riser up to the same height
If m is the mass of ball then impulse imparted is given by 


Thus impulse imparted by gravity and Floor will have same magnitude of impulse but direction will be opposite to each other.
 
        
             
        
        
        
Answer:
<h2>
d₂ = 3d</h2><h2>
The diameter of the second wire is 3 times that of the initial wire.</h2>
Explanation:
Using the formula for calculating the resistivity of an object to find the diameter. 
Resistivity P = RA/L
R is the resistance of the material
A is the cross sectional area
L is the length of the material
Since A = πd²/4
P = R( πd²/4)/L
P = Rπd²/4L ... 1
If the second wire of the same material and length is found to have resistance R/9, the resistivity of the second material will be;
P₂ = (R/9)A₂/L₂
P₂ = (R/9)(πd₂²/4)/L₂ 
P₂ = (Rπd₂²/36)/L₂ 
P₂ = (Rπd₂²)/36L₂ 
Since the length and resistivity are the same;
P = P₂  and L =L₂ 
Equating 1 and 2;
Rπd²/4L =  (Rπd₂²)/36L₂ 
Rπd²/4L =  (Rπd₂²)/36L
d² = d₂²/9
d₂² = 9d²
Taking the square root of both sides;
√d₂² = √9d²
d₂ = 3d
Therefore the diameter of the second wire is 3 times that of the initial wire
 
        
             
        
        
        
I think, I do think.. that it is D. 
Wouldn't it be simple to divide 5 from 20, that would equal 4. 
4 earthworms per square meter.