Explanation:
I think the third one coz it's so good
Given Information:
Current in loop = I = 62 A
Magnitude of magnetic field = B = 1.20x10⁻⁴ T
Required Information:
Radius of the circular loop = r = ?
Answer:
Radius of the circular loop = 0.324 m
Explanation:
In a circular loop of wire with radius r and carrying a current I induces a magnetic field B which is given by
B = μ₀I/2r
Please note that for an infinitely straight long wire we use 2πr whereas for circular loop we use 2r
Where μ₀= 4πx10⁻⁷ is the permeability of free space
Re-arranging the equation yields
r = μ₀I/2B
r = 4πx10⁻⁷*62/2*1.20x10⁻⁴
r = 0.324 m
Therefore, the radius of this circular loop is 0.324 m
Answer:
The mailbag will take 2.44 seconds to reach the ground.
Explanation:
The height of a helicopter above the ground is given by:

Height of helicopter at t = 2.10 seconds

The helicopter releases a small mailbag from the height of 29.17 m.
The initial velocity of mailbag = u = 0 m/s
Duration in which mailbag will reach the ground = T
Acceleration due to gravity = g = 
Using second equation of motion ;

We have , s = 29.17
u = 0 m/s
t = T

Solving for T, we gte :
T = 2.44 seconds
The mailbag will take 2.44 seconds to reach the ground.
The equation you would use here is F=ma, where F is the force in Newtons, m is the mass in kilograms (must be in kilograms in order for the units to match on both sides), and a is acceleration in meters per second squared. Therefore, you do: 65kg x .3m/s^2= FF. That'll give you the answer.