🧲 ONLYGYAANI VIRTUAL PHYSICS LAB

Magnetic Field & Compass Lab

Drag the compass anywhere around the bar magnet and watch its needle rotate according to the local magnetic field direction.

🧲 Bar Magnet North and South poles

🧭 Draggable Compass Move it freely

〰️ Field Direction Calculated continuously

📊 Field Strength Changes with position

🧲 Interactive Magnetic Field Explorer

🧭 DRAG THE COMPASS
Move it around the magnet and watch the needle rotate.

● FIELD LINES ON

BAR MAGNET

NORTH POLE

SOUTH POLE

N S E W

↔ DRAG

🎛 Experiment Controls

🧲 Magnet Strength 60%

Weak Strong

🧭 Quick Compass Positions

Magnet Strength 60%

Field Direction —

Relative Field —

Distance —

Drag the compass around the magnet. The red end of the needle follows the calculated local magnetic-field direction.

🎯 Aim

To investigate the direction and relative strength of the magnetic field surrounding a bar magnet using a movable compass.

📘 Theory

A bar magnet creates a magnetic field in the surrounding space. A compass needle experiences a turning effect and tends to align with the local magnetic field.

Field direction:
Outside a bar magnet, the conventional magnetic-field direction is from the North pole toward the South pole.

🧭 How the Compass Works

The compass contains a small magnetic needle. Its north-seeking end aligns approximately with the direction of the magnetic field at the compass location.

Move the compass to different places around the magnet. The needle should rotate continuously rather than simply point in one fixed direction.

Remember:
The field-line drawings are a visual model. A magnetic field exists throughout the surrounding region; it is not made of physical lines.

📊 Observation Table

Trial	X Position	Y Position	Direction	Relative Field	Distance	Strength
No observations recorded.

🧪 Student Activity

Activity 1
Drag the compass slowly around the entire magnet. Watch how the needle turns.

Activity 2
Compare the field near a pole with the field far from the magnet.

Activity 3
Set magnet strength to 20%, then 60%, then 100%. Compare the relative field reading.

📝 Procedure

Observe the bar magnet and its N and S poles.
Keep the magnetic field lines visible initially.
Drag the compass above the magnet.
Observe the red end of the compass needle.
Move the compass near the North pole.
Move it near the South pole.
Move it below the magnet.
Compare the field direction at each location.
Change the magnet strength.
Record several observations.

🔍 Expected Observations

The compass direction changes continuously as it moves around the magnet.

The calculated relative field becomes stronger near the magnetic poles and weaker as the compass moves farther away.

Increasing the magnet-strength control increases the relative field reading without changing the basic field pattern.

💡 Try hiding the field lines and predict the field direction using only the compass.

✅ Experiment Result

The compass needle changes direction as it moves through different positions around the bar magnet. This demonstrates that a magnetic field has both direction and strength. The external field is conventionally represented as travelling from the North pole toward the South pole.