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Gravitational potential energy is the energy an object possesses because of its position in a gravitational field. Since the force required to lift it is equal to its weight, it follows that the gravitational potential energy is equal to its weight times the height to which it is lifted. (i.e, P.E\(_g\) = \omegah, where \omega = mg)

For the first copper rod: \(L_0 = 5 \, \text{m} = 5000 \, \text{mm}, \quad \Delta T = 10 \, \text{^\circC}, \quad \Delta L = 1 \, \text{mm}\) Coefficient of linear expansion \( \alpha \): \(\alpha = \frac{1 \, \text{mm}}{5000 \, \text{mm} \cdot 10} = \frac{1}{50000} \, \text{mm}^{-1}\) For the second copper rod: \(L_0 = 2.5 \, \text{m} = 2500 \, \text{mm}, \quad \Delta T = 5 \, \text{^\circC}\) Expansion: \(\Delta L = L_0 \cdot \alpha \cdot \Delta T = 2500 \, \text{mm} \cdot \frac{1}{50000} \, \text{mm}^{-1} \cdot 5 = 0.25 \, \text{mm}\) The second copper rod will expand by: \(0.25 \, \text{mm}\)

- Topping is done with distilled water - Naked flame should be avoided when charging the battery - Direct connection of wires to the terminals should be avoided.

RH = mass of water vapour in volume of air mass of water vapour for saturation RH = m M = 0.05 0.15 \times 100 = 5 0.15 = 500 15 = 33.33%

Dispersion is due to different refractive indices speeds and wavelengths.

- Waves are produced by vibration - Waves transmit energy along the medium - Particles of a medium vibrate with the wave motion without the entire medium - Some waves require medium for transmission (mechanical).

P = F A = mg A = (ρ \times v) \times g A = ρ \times (A \times h) \times g A P = 100 \times 2 \times 10\(^{-2}\) \times 10 = 20 N/m\(^2\)

The bob of a pendulum will have maximum kinetic energy and minimum potential energy at the lowest point of its swing.

all the parallel forces must be equal in magnitude and direction

- the total energy at any point is a combination of the P.E and K.E - the sum of PE and KE at any point is always constant not the ratio of P.E to K.E

Efficiency of conduction in liquids and gases compared to solids is less efficient than solid.

P = Pa + ρgh = (1.00 \times 10\(^5\)) + (950 \times 10 \times 1000) P = 10\(^5\) + (95 \times 10\(^5\)) = 10\(^5\)(1 + 95) = 96 \times 10\(^5\) P = 9.6 \times 10\(^6\) N/m\(^2\)

First condition

- I & II are in neutral equilibrium. They will roll continuously on the table - III is a body with high centre of gravity (unstable) - IV is a body with high centre of gravity (stable)

The volume of object is the same as the volume of liquid displaced in a container such as measuring cylinder.