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For anybody falling through a viscous liquid, at its terminal velocity. the resultant force acting on its is zero. from the equation: Mg - v - u = 0. where v = viscous drag U = upthrust Mg = weight of the body. ∴ 36 x 10 - 260 - U = 0 ∴ U = 360 - 260 = 100N Upthrust on the body = 100N.

Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration. This movement occurs due to the random motion of particles, leading to an even distribution of substances over time.

Evaporation is a process by which molecules undergo a spontaneous transition from the liquid phase to the gaseous phase

Melting (I): This process involves the breaking of intermolecular forces as a solid turns into a liquid, reflecting the molecular structure of matter. Boiling (II): Similar to melting, boiling involves the transition from liquid to gas, indicating how molecules gain energy and move apart Conduction (IV): This is the process of heat transfer through collisions between molecules, demonstrating how molecular interactions lead to energy transfer.

When very hot water is poured into the thick glass tumbler, the inner surface of the glass heats up and expands more quickly than the outer part. This creates stress due to uneven expansion, leading to cracking. In contrast, the thin glass tumbler is less prone to this issue because it heats more uniformly.

Radio waves are used to transmit signals between satellites and ground stations because they can travel long distances and effectively penetrate the atmosphere.

For the device rated 2000 W, 250 V, implies that current I, flowing is given by the relation Power = IV I = (power)/v = (200)/250 = 8A. ∴ the most suitable fuse for the device is 8A

Magnetic poles always exist in pairs. It is not possible to produce just an isolated north pole or an isolated south pole. If a bar magnet is broken into two pieces, each piece will have a north and south pole.

For a car battery rated 45 AH, being charged by a charger of 2.5 A rating, the time for the battery to be fully charged is given by: T = (45)/2.5 = 18 hrs

The electric force experienced in an electric field of intensity E is given by: F = qE: where q = the test charge. E = F/Q = 0.4/10-10 = 0.4 X 10-10 = 4.0 X 109 NC-1

The charge must be opposite in sign, since the positive charges will deflect to the negative plate, and the negative charge to the positive plate

To determine the deceleration of the motorcyclist, we can use the kinematic equation that relates initial velocity, final velocity, acceleration, and distance: \(v^2 = u^2 + 2as\) Where: \( v \) = final velocity (0 m/s, since he stops at the traffic light), \( u \) = initial velocity (30 m/s), \( a \) = acceleration (deceleration, which will be negative) \( s \) = distance (50 m) Substituting the values into the equation, we rearrange it to solve for \( a \): \(0 = (30)^2 + 2a(50)\) Calculating \( (30)^2 \): \(0 = 900 + 100a\) Now, rearranging for \( a \): \(100a = -900\) \(a = -\frac{900}{100} = -9 \, \text{m/s}^2\) The deceleration of the motorcyclist is \( \mathbf{9 \, m/s^2} \).

For the two point charges, the magnitude of the electrostatic force between them is given by the equation: F ∝ 1/r2, and if the distance is increased by a factor of 4, that is new distance = 4r, then, new force F ∝ 1/(4r)2 = ∝ 1/16r2 Thus it will be 1/16 of the former value

The fig above shows a conventional transistor, showing the three basic features, the Base, the Emitter and the collector. Thus comparing this with the figure in the question it implies that P = Emitter, Q = Base and R = collector

\( ^{235} _{92}U + ^1 _0n → ^{144} _{56}Ba + ^{90} _{36}Kr +2^1_0X \) In the reaction above, balancing the left with the right shows that X is a neutron