Answer:
the time taken for the ball to hit the ground is 0.424 s
Explanation:
Given;
velocity of the ball, u = 5 m/s
height of the house which the ball was kicked, h = 3m
Apply kinematic equation;
h = ut + ¹/₂gt²
where;
h is height above ground
u is velocity
g is acceleration due to gravity
t is the time taken for the ball to hit the ground
Substitute the given values and solve for t
3 = 5t + ¹/₂(9.8)t²
3 = 5t + 4.9t²
4.9t² + 5t -3 = 0
a = 4.9, b = 5, c = -3
Solve for t using formula method

Answer:
0.012 N
Explanation:
The formula to apply is that adopted from the Ampere law which is;
F= μ* I₁*I₂*l /2πd where
F is force that one conductor exerts on the other.
μ = magnetic permeability of free space = 4π×10⁻⁷ T. m/A
I₁ = current in conductor one=10 A
I₂ = current in conductor two= 10 A
l= length of conductor= 3 m
d= distance between the conductors = 5 mm = 0.005 m
Applying the values in the equation
F= 4π×10⁻⁷ *10*10*3 / 2π*0.005
F= 6 * 10⁻⁵ / 0.005
F=0.012 N