<h3><u>Answer;</u></h3>
<em>The voltage is zero</em>
<h3><u>Explanation;</u></h3>
- <em><u>Voltage is the potential difference between two points in a circuit or the electromotive force in a given circuit and is expressed in volts (V). </u></em>
- Voltage is measured by a device called voltmeter that is always connected in parallel with the current source.
- <em><u>When voltage is measured between two points on a wire in a circuit with zero or no resistance in between the two points then the voltage will be zero</u></em><em>. </em>From the ohm's Law, voltage is given the product of resistance and current and thus if the resistance is zero then the voltage will be zero.
The visible spectrum<span> is portion of the </span>electromagnetic spectrum<span> that is </span>visible <span>to the </span><span>human eye.
</span>gamma rays, <span>sound waves, </span><span>microwaves are not the part of spectrum of light, whereas color is the portion of spectrum of light.</span>
Answer:
μ = 0.350
Explanation:
For the person to able to move the box, the force exerted by the person on the box must equal the force exerted by the box:
In this case, force can be calculated as a product of mass (m) by the acceleration of gravity (g) and the coefficient of static friction (μ):
Therefore, for the person to be able to push the box horizontally, the coefficient of static friction between the box and the floor should not be higher than 0.350.
Answer:
b. 1.9 Ω
Explanation:
Here is the complete question
A series LR circuit contains an emf source of 14 V having no internal resistance, a resistor, a 34 H inductor having no appreciable resistance, and a switch. If the emf across the inductor is 80% of its maximum value 4.0 s after the switch is closed, what is the resistance of the resistor? a. 1.5 ? b. 1.9 ? c. 5.0 ? d. 14 ?
Solution
The voltage across the inductor V is
where V₀ = emf of source = 14 V, R = resistance, L = inductance = 34 H and t = time
Given that V = 80% of its maximum value after 4.0 s, this implies that V = 80 % of V₀ = 0.8V₀ and t = 4.0 s
Since and V = 0.8V₀.
Since we need to find R, we make R subject of the formula, we have
taking natural logarithm of both sides, we have
㏑(V/V₀) = -Rt/L
R = -L㏑(V/V₀)/t
Substituting the values of the variables into the equation, we have
R = -34㏑(0.8V₀/V₀)/4.0 s
R = -34㏑(0.8)/4.0 s
R = -34 × -0.2231/4.0 s
R = 7.587/4
R = 1.896 Ω
R ≅ 1.9 Ω
So, B is the answer