Answer:
Explanation:
We shall solve this question with the help of Ampere's circuital law.
Ampere's ,law
∫ B dl = μ₀ I , B is magnetic field at distance x from the axis within wire
we shall find magnetic field at distance x . current enclosed in the area of circle of radius x
= I x π x² / π R²
= I x² / R²
B x 2π x = μ₀ x current enclosed
B x 2π x = μ₀ x I x² / R²
B = μ₀ I x / 2π R²
Maximum magnetic B₀ field will be when x = R
B₀ = μ₀I / 2π R
Given
B = B₀ / 3
μ₀ I x / 2π R² = μ₀I / 2π R x 3
x = R / 3
b ) The largest value of magnetic field is on the surface of wire
B₀ = μ₀I / 2π R
At distance x outside , let magnetic field be B
Applying Ampere's circuital law
∫ B dl = μ₀ I
B x 2π x = μ₀ I
B = μ₀ I / 2π x
Given B = B₀ / 3
μ₀ I / 2π x = μ₀I / 2π R x 3
x = 3R .
Answer:
Thermal energy of an isolated system changes with time If the mechanical energy of that system is constant according to the first law of thermodynamics, which states that thermal energy of an isolated system can still change as long as the total energy of that system does not change.
Explanation:
Answer:
Explanation:
Power is related to energy by the following relationship:
where
P is the power used
E is the energy used
t is the time elapsed
In this problem, we know that
- the power of the fan is P = 120 W
- the fan has been running for one hour, which corresponds to a time of
So we can re-arrange the previous equation to find E, the energy (in the form of thermal energy) released by the fan:
Explanation:
If box weight 25N on ground
MA=F
M(10)=25
M=2.5Kg
Answer:
I= 3.5 amps
Explanation:
Step one:
given data
rating of resistor R= 8 ohms
power P= 100W
Required
The current I
Step two
Yet this power is also given by
make I subject of the formula we have
substitute
