Answer:B.As the north pole of the electromagnet nears the south pole of the permanent magnet, the current reverses and the poles of the magnets then repel.
Explanation:
Answer:
Explanation:
Let the velocity after first collision be v₁ and v₂ of car A and B . car A will bounce back .
velocity of approach = 1.5 - 0 = 1.5
velocity of separation = v₁ + v₂
coefficient of restitution = velocity of separation / velocity of approach
.8 = v₁ + v₂ / 1.5
v₁ + v₂ = 1.2
applying law of conservation of momentum
m x 1.5 + 0 = mv₂ - mv₁
1.5 = v₂ - v₁
adding two equation
2 v ₂= 2.7
v₂ = 1.35 m /s
v₁ = - .15 m / s
During second collision , B will collide with stationary A . Same process will apply in this case also. Let velocity of B and A after collision be v₃ and v₄.
For second collision ,
coefficient of restitution = velocity of separation / velocity of approach
.5 = v₃ + v₄ / 1.35
v₃ + v₄ = .675
applying law of conservation of momentum
m x 1.35 + 0 = mv₄ - mv₃
1.35 = v₄ - v₃
adding two equation
2 v ₄= 2.025
v₄ = 1.0125 m /s
v₃ = - 0 .3375 m / s
Electric current can be generated by moving a metal wire through a magnetic field It is also different than static electricity, which is the accumulation of charges on a surface. Electric generators rotate a coil of wires through a magnetic field.
Answer:
Number of electrons, 
Explanation:
Given that,
Charge on the fur, 
A piece of amber is charged by rubbing with a piece of fur. We need to find the electrons were added to the amber. It can be calculated using the quantization of charge as
q = n × e
Where
n is the number of electrons
e is the charge on electron
So, number of electrons are added to the amber. Therefore, this is the required solution.
