The correct answer is A. the magnet to become stronger
The stronger the electric current in the piece of metal, the stronger the magnetic field will be.
From conservation of energy, the height he will reach when he has gravitational potential energy 250J is 0.42 meters approximately
The given weight of Elliot is 600 N
From conservation of energy, the total mechanical energy of Elliot must have been converted to elastic potential energy. Then, the elastic potential energy from the spring was later converted to maximum potential energy P.E of Elliot.
P.E = mgh
where mg = Weight = 600
To find the height Elliot will reach, substitute all necessary parameters into the equation above.
250 = 600h
Make h the subject of the formula
h = 250/600
h = 0.4167 meters
Therefore, the height he will reach when he has gravitational potential energy 250J is 0.42 meters approximately
Learn more about energy here: brainly.com/question/24116470
Hello! Assuming that the only force acting on the mass is 30N...
Fnet = 30N
Fnet = ma (mass x acceleration)
ma = 30N
a = 30N / m
a = 30N / 7kg
a = 4.2857 m/s^2
a = 4 m/s^2
I hope this helps!
The correct answer is silver metal.
Conductivity measures the ability of a material or a metal to transmit energy, conductivity may be electrical, thermal or acoustical conductivity. The most electrical conductive element is silver, followed by copper and Gold. Silver also has the highest thermal conductivity as compare to any element. However, copper and Gold are more often used in electrical applications since copper is less expensive and gold has a much higher corrosion resistance.
Complete question:
A 45-mH ideal inductor is connected in series with a 60-Ω resistor through an ideal 15-V DC power supply and an open switch. If the switch is closed at time t = 0 s, what is the current 7.0 ms later?
Answer:
The current in the circuit 7 ms later is 0.2499 A
Explanation:
Given;
Ideal inductor, L = 45-mH
Resistor, R = 60-Ω
Ideal voltage supply, V = 15-V
Initial current at t = 0 seconds:
I₀ = V/R
I₀ = 15/60 = 0.25 A
Time constant, is given as:
T = L/R
T = (45 x 10⁻³) / (60)
T = 7.5 x 10⁻⁴ s
Change in current with respect to time, is given as;
![I(t) = I_o(1-e^{-\frac{t}{T}})](https://tex.z-dn.net/?f=I%28t%29%20%3D%20I_o%281-e%5E%7B-%5Cfrac%7Bt%7D%7BT%7D%7D%29)
Current in the circuit after 7 ms later:
t = 7 ms = 7 x 10⁻³ s
![I(t) = I_o(1-e^{-\frac{t}{T}})\\\\I =0.25(1-e^{-\frac{7*10^{-3}}{7.5*10^{-4}}})\\\\I = 0.25(0.9999)\\\\I = 0.2499 \ A](https://tex.z-dn.net/?f=I%28t%29%20%3D%20I_o%281-e%5E%7B-%5Cfrac%7Bt%7D%7BT%7D%7D%29%5C%5C%5C%5CI%20%3D0.25%281-e%5E%7B-%5Cfrac%7B7%2A10%5E%7B-3%7D%7D%7B7.5%2A10%5E%7B-4%7D%7D%7D%29%5C%5C%5C%5CI%20%3D%200.25%280.9999%29%5C%5C%5C%5CI%20%3D%200.2499%20%5C%20A)
Therefore, the current in the circuit 7 ms later is 0.2499 A