Answer:She can increase the number of wire loops
Explanation: When the number of loops of wire ( usually around the iron ) increases, the strength of the electromagnet is increased.
According to the equation
B=μ₀ N I
Where
μ₀ = permeability of the core
N= Number of turns of the coil
I= Current flowing through the coil
From the equation above , we can see that The strength of an electromagnet depends the amount of current, no of turns of coil and the permeability core of coil. we can now say that Increasing the number of wire loops increases the strength of electromagnet.
Therefore, Lisa should increase the number of wire loops to increase the strength of the electromagnet
A greater weight so the object has greater weight
B.
increases as the tension of the string increases
Answer:
Explanation:
Given that, .
Frequency
f = 60Hz
Number of turns
N = 125turns
Surface area of coil
A = 3 × 10^-2 m²
Magnetic field
B = 0.12T
Voltage peak to peak? I.e the EMF
EMF is given as
ε = —dΦ/dt
Where Φ is magnetic flux and it is given as
Φ = NBA Cosθ
Where N is number of turns
B is magnetic field
A is the cross sectional area
And θ is the resulting angle from the dot product of area and magnetic field
Where θ =ωt and ω = 2πf
Then, θ = 2πft
So, your magnetic flux becomes
Φ = NBA Cos(2πft)
Now, dΦ / dt = —NBA•2πf Sin(2πft)
dΦ / dt = —2πf • NBA Sin(2πft)
So, ε = —dΦ/dt
Then,
ε = 2πf • NBA Sin(2πft)
So, the maximum peak to peak emf will occur when the sine function is 1
I.e Sin(2πft) = 1
So, the required peak to peak emf is
ε = 2πf • NBA
Substituting all the given parameters
ε = 2π × 60 × 125 × 0.12 × 3 × 10^-2
ε = 169.65 Volts
The peak to peak voltage is 169.65 V
I believe it's Mercury, because the only other option would be Pluto and it's not even considered a planet anymore
Hope this helps