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Magnifying Glass Tilted Right

Theme D - Fields

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Rocket

Theme A - Space, Time & Motion

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Thermometer

Theme B - The Particulate Nature Of Matter

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Water Wave

Theme C - Wave Behaviour 

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Microscope

Theme E - Nuclear & Quantum Physics

Magnetic force on a wire inside a magnetic field is directly related to:

<ul>
	<li>📏 Length (L) of the wire</li>
	<li>⚡ Current (I) in the wire</li>
</ul>

<ul>
	<li>Can&#39;t just use force to define it. Why? Because the force depends on BOTH current and length.</li>
	<li>Definition 📖: Magnetic field strength = Force on a short section of wire (or &quot;element&quot;) carrying current ⚡ AND at right angles to the magnetic field.</li>
	<li>Formula 👉: B = F / (I &times; L)
	<ul>
		<li>Where B = magnetic field strength</li>
		<li>F = force on the wire</li>
		<li>I = current</li>
		<li>L = length of the wire</li>
	</ul>
	</li>
	<li>Unit: Tesla (T) 🎖️
	<ul>
		<li>Can think of Tesla as: NA&minus;1m&minus;1 or as basic units kgs&minus;2A&minus;1</li>
	</ul>
	</li>
	<li>Earth&#39;s magnetic field: Roughly 10&minus;4 T 🌍</li>
	<li>Extreme example: Some neutron stars have magnetic fields around 100GT! ⭐️</li>
</ul>

<ul>
	<li>If everything (field lines, wire, current) is at a right angle: F = BIL</li>
	<li>If the wire is tilted (at an angle &theta;): Use the component of the current that&#39;s at 90&deg; to the field. Formula 👉: F = BIL sin &theta;
	<ul>
		<li>Here, &theta; is between the charge&#39;s movement direction (or current direction) and the field lines.</li>
	</ul>
	</li>
</ul>

<ul>
	<li>Current, I = q/t (where q = charge and t = time)</li>
	<li>Force formula when considering charge: F = qvB sin &theta;</li>
</ul>

Goal: Estimate the magnetic force acting on standard lab currents.

<ul>
	<li>Tools: Flat magnets, top-pan balance, power supply, straight lead.</li>
	<li>Method
	<ul>
		<li>Measure how force changes with the length of the conductor &amp; current size.</li>
		<li>Use the current as the independent variable, measure the force on the balance.</li>
		<li>Trick: Reverse current, take readings, add them up (double the answer).</li>
	</ul>
	</li>
</ul>

<ul>
	<li>Example 2: A particle with mass m, charge q, speed v in a magnetic field has force F. If another particle has double the charge and speed, the force is 4F!</li>
	<li>Example 3: Horizontal wire, current of 3.5A, in a magnetic field, 14mN force acts on it:
	<ul>
		<li>Magnetic field strength is 0.10T.</li>
		<li>Magnetic force direction? Using Fleming&rsquo;s left-hand rule, it&#39;s downwards!</li>
	</ul>
	</li>
	<li>Example 4: Alpha particle in a magnetic field. Calculated acceleration is a whopping 4.85 &times; 1010 ms&minus;2! This only changes its direction, not speed.</li>
</ul>

Fun Real-World Analogy 🍦: Think of magnetic force like toppings on your ice cream. The amount of toppings (force) depends on the size of your ice cream scoop (length of the wire) and the type of ice cream (current). If you tilt your ice cream, you&#39;ll get toppings (force) only where it faces upwards. And always remember, too much of toppings (neutron star-level magnetic field) can be overwhelming!

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Keep exploring, future physicist! 🌌🔭🌟

Theme D - Fields

Unlock The Secrets Of Magnetic Force: How Current & Length Impact Strength

Table of content

What Makes Magnetic Force Tick? 🧲

Defining Magnetic Field Strength 💪

Calculating Magnetic Force 🤔

Unlock the Full Content!

Theme D - Fields

Unlock The Secrets Of Magnetic Force: How Current & Length Impact Strength

Table of content

What Makes Magnetic Force Tick? 🧲

Defining Magnetic Field Strength 💪

Calculating Magnetic Force 🤔

Unlock the Full Content!