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Given:

• Area of head = 15 cm × 15 cm

• So, $A = 15 × 15 = 225 \text{ cm}^2$A=15×15=225 cm2

Now we need to find the weight of air above this area — that means we must consider air pressure.

Step 1: Standard atmospheric pressure

At sea level,

$$1 \text{ atmosphere} = 1.013 \times 10^5 \text{ N/m}^2$$1 atmosphere=1.013×105 N/m2

Step 2: Convert area from cm² to m²

$$225 \text{ cm}^2 = 225 × 10^{-4} \text{ m}^2 = 0.0225 \text{ m}^2$$225 cm2=225×10−4 m2=0.0225 m2

Step 3: Force on the head due to air pressure

$$\text{Force} = \text{Pressure} × \text{Area}$$Force=Pressure×Area $$F = 1.013 × 10^5 × 0.0225 = 2280 \text{ N (approximately)}$$F=1.013×105×0.0225=2280 N (approximately)

Step 4: Convert force to equivalent weight (mass)

$$\text{Weight} = mg \implies m = \frac{F}{g}$$Weight=mg⟹m=gF

Using $g = 9.8 \text{ m/s}^2$g=9.8 m/s2:

$$m = \frac{2280}{9.8} ≈ 232.65 \text{ kg}$$m=9.82280≈232.65 kg

✅ Final Answer:
You are carrying approximately 230 kilograms of air on your head due to atmospheric pressure!

Electrostatic force.When the balloon is rubbed with a piece of synthetic cloth, it becomes electrically charged. When this charged balloon is brought near a neutral wall, it induces opposite charges on the surface of the wall. The attraction between the charged balloon and the induced opposite charges on the wall causes the balloon to stick.

1. Forces acting on the bucket:

There are 2 main forces acting on the bucket:

Why does the bucket not move?

Ans. The bucket is not moving because both forces are equal and opposite.