Answer:
220 A
Explanation:
The magnetic force on the floating rod due to the rod held close to the ground is F = BI₁L where B = magnetic field due to rod held close the ground = μ₀I₂/2πd where μ₀ = permeability of free space = 4π × 10⁻⁷ H/m, I₂ = current in rod close to ground and d = distance between both rods = 11 mm = 0.011 m. Also, I₁ = current in floating rod and L = length of rod = 1.1 m.
So, F = BI₁L
F = (μ₀I₂/2πd)I₁L
F = μ₀I₁I₂L/2πd
Given that the current in the rods are the same, I₁ = I₂ = I
So,
F = μ₀I²L/2πd
Now, the magnetic force on the floating rod equals its weight , W = mg where m = mass of rod = 0.10kg and g = acceleration due to gravity = 9.8 m/s²
So, F = W
μ₀I²L/2πd = mg
making I subject of the formula, we have
I² = 2πdmg/μ₀L
I = √(2πdmg/μ₀L)
substituting the values of the variables into the equation, we have
I = √(2π × 0.011 m × 0.1 kg × 9.8 m/s²/[4π × 10⁻⁷ H/m × 1.1 m])
I = √(0.01078 kgm²/s²/[2 × 10⁻⁷ H/m × 1.1 m])
I = √(0.01078 kgm²/s²/[2.2 × 10⁻⁷ H])
I = √(0.0049 × 10⁷kgm²/s²H)
I = √(0.049 × 10⁶kgm²/s²H)
I = 0.22 × 10³ A
I = 220 A
Answer:
Left to right and top to bottom
Explanation:
On the periodic table, the properties repeat from left to right and from top to bottom.
Periodic properties have a pattern from the top to the bottom or down a group or family.
Also, across the period from left to right, they also show a repeating pattern.
- Certain properties increase from left to right and decreases from top to bottom. E.g. electronegativity.
- Also, some properties decreases from left to right and increases from top to bottom e.g. atomic radius.
Answer:
Answered
Explanation:
x= 0.02 m
E_p= 10.0 J
E_p= 0.5kx^2
10= 0.5k(0.02)^2
solving we get
K= 50.0 N/m
Now
E'_p= 0.5kx'^2
E'_p= 0.5×50×(0.04)^2
E'_p=40 J
b) potential energy is a scalar quantity and it only depends magnitude and not direction so it will remain same in compression and expansion both
c) 20 J = 0.5×50,000×x^2
solving
x= 0.028 m
d) k is 50.0 N/m from above calculation
Answer:
<em>The penny will hit the ground at 6.39 seconds</em>
Explanation:
<u>Free Fall</u>
The penny is dropped from a height of y=200 m. The equation of the height on a free-fall motion is given by:
Where 
, and t is the time.
Solving for t:
Using the value y=200:
t=6.39 sec
The penny will hit the ground at 6.39 seconds
The correct answer is A.
The coefficient of absorption of material A is 30%. So, the material will absorb 30% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 70% energy.
The coefficient of absorption of material B is 47%. So, the material will absorb 47% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 53% energy.
The coefficient of absorption of material C is 62%. So, the material will absorb 62% energy of the incident wave falling on it. Thus, the reflected wave will carry the rest 28% energy.
Hence, material C would be the best, because the percentage of the energy in an incident wave that remains in a reflected wave from this material is the smallest.
