Answer:
(a) the speed of the block after the bullet embeds itself in the block is 3.226 m/s
(b) the kinetic energy of the bullet plus the block before the collision is 500J
(c) the kinetic energy of the bullet plus the block after the collision is 16.13J
Explanation:
Given;
mass of bullet, m₁ = 0.1 kg 
initial speed of bullet, u₁ = 100 m/s
mass of block, m₂ = 3 kg 
initial speed of block, u₂ = 0
Part (A)
Applying the principle of conservation linear momentum, for inelastic collision;
m₁u₁ + m₂u₂ = v(m₁ + m₂)
where;
v is the speed of the block after the bullet embeds itself in the block
(0.1 x 100) + (3 x 0) = v (0.1 + 3)
10 = 3.1v
v = 10/3.1
v = 3.226 m/s
Part (B)
Initial Kinetic energy
Ki = ¹/₂m₁u₁² + ¹/₂m₂u₂²
Ki =  ¹/₂(0.1 x 100²) +  ¹/₂(3 x 0²)
Ki = 500 + 0
Ki = 500 J
Part (C)
Final kinetic energy
Kf = ¹/₂m₁v² + ¹/₂m₂v²
Kf = ¹/₂v²(m₁ + m₂)
Kf = ¹/₂ x 3.226²(0.1 + 3)
Kf = ¹/₂ x 3.226²(3.1)
Kf = 16.13 J
 
        
             
        
        
        
Answer:
0.012 J
Explanation:
We are given:
q = 0.0080C
Potential difference =  1.5V
W=qV
Substituting the values into the equation:
W=0.0080*1.5= 0.012J
 
        
             
        
        
        
Answer: D
Explanation: Resistance of current in a wire is directly proportional to the length of the wire and inversely proportional to the cross - sectional area of the wire. That is,
R = (rho × L)/A
Where
L = length of the wire 
A = cross sectional Area of the wire 
rho = resistivity = proportionality constant which depends on the quality of the wire.
Therefore, Resistance and resistivity are related by a:
proportionality constant dependent on the identity of the material.
 
        
             
        
        
        
Answer:
Explanation:
 Let the magnetic field be
B = 
For magnetic force , the expression is 
F = L ( I x B )
= 1.5 ( 24i x  )
 )
F = 36 B_y k - 36 B_z j 
Given 
F = 3 j + 2 k 
Equating equal terms 
we have 
B_y = 2 / 36 , B_z = - 3 / 36 
Now the direction of current is changed to y direction 
so F = ![1.5[ 24j \times ( B_xi +B_yj +B_z k )]](https://tex.z-dn.net/?f=1.5%5B%2024j%20%5Ctimes%20%28%20B_xi%20%2BB_yj%20%2BB_z%20k%20%29%5D)
Given 
F = - 3 i - 2 k 
Equating equal terms 
we have 
B_x = 2 / 36 , B_z = - 3 / 36 
So B = 2/36 i + 2/36 j - 3/ 36 k 
Magnitude of B 
= 4.1 / 36 T