Answer:
104
Explanation:
U = Energy stored in the solenoid = 6.00 μJ = 6.00 x 10⁻⁶ J
i = current flowing through the solenoid = 0.4 A
L = inductance of the solenoid
Energy stored in the solenoid is given as
U = (0.5) L i²
6.00 x 10⁻⁶ = (0.5) L (0.4)²
L = 75 x 10⁻⁶
Inductance is given as
l = length of the solenoid = 0.7 m
N = number of turns
r = radius = 5.00 cm = 0.05 m
Area of cross-section is given as
A = πr²
A = (3.14) (0.05)²
A = 0.00785 m²
Inductance is given as


N = 73
Winding density is given as
density = n = 
n = 
n = 104
Answer:
The definition of acceleration is: Acceleration is a vector quantity that is defined as the rate at which an object changes its velocity. An object is accelerating if it is changing its velocity.
Explanation:
Like this:
1). Ignore the 22.7 m/s horizontal speed. It doesn't make a bit of difference, and the answer doesn't depend on it. (A bullet fired horizontally from a rifle and another bullet dropped from the end of the rifle barrel at the same time both hit the ground at the same time.)
2). Calculate how long it takes an object dropped from rest to fall 42.3 m. Use the "dropped from rest" formula:
Distance = (1/2) (acceleration) (time)²
3). In the formula, "acceleration" is the acceleration of gravity. If this story happened on Earth, then use the acceleration of gravity on Earth. That's 9.81 m/s² .
I wish I could make it more complicated for you, but I don't know how.