Answer:
he polarity of the electromagnet is determined by the direction the current. The north pole of the electromagnet is determined by using your right hand. Wrap your fingers around the coil in the same direction as the current is flowing (conventional current flows from + to -).
Explanation:
Answer:
Now e is due to the ring at a
So
We say
1/4πEo(ea/ a²+a²)^3/2
= 1/4πEo ea/2√2a³
So here E is faced towards the ring
Next is E due to a point at the centre
So
E² = 1/4πEo ( e/a²)
Finally we get the total
Et= E²-E
= e/4πEo(2√2-1/2√2)
So the direction here is away from the ring
Answer:
q = 2.65 10⁻⁶ C
Explanation:
For this exercise we use Coulomb's law
F =
In this case they indicate that the load is of equal magnitude
q₁ = q₂ = q
the force is attractive because the signs of the charges are opposite
F = 
q = 
we calculate
q = 
q = 
Ra 7 10-12
q = 2.65 10⁻⁶ C
Answer:
1470kgm/s
Explanation:
Given parameters:
Mass of the rock = 50kg
Time taken for the free fall = 3s
Unknown:
Change in momentum = ?
Solution:
The change in momentum will be difference between the ending momentum and finishing momentum.
Momentum is the product of mass and velocity
Momentum = mass x velocity
Initial momentum = 0, the velocity is 0
Final momentum = mass x final velocity
let us find the final velocity;
V = U + gt
V is the final velocity
U is the initial velocity
g is the acceleration due to gravity = 9.8m/s²
t is the time
V = 0 + 9.8x3 = 29.4m/s
So;
Change in momentum = 50 x 29,4 = 1470kgm/s
