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With an increase in pressure, the viscosity of liquids except water increases while that of gases is practically independent of pressure.

Both X-rays and gamma rays are uncharged electromagnetic waves with similar high energy, but they differ mainly in their origin.

Power, P = I2R; and I = E/R But effective Parallel resistance: is given by: 1/R = 1/6 + 1/3 = 1+2/6 = 3/6 => R = 6/3 = 2Ω Current I = E/R = 12/2 = 6A But I1 = (R1/R1+R2) x 1 = 3/9 x 6 = 2A again I1 = (R1/R1+R2) x 1 = 6/9 x 6 = 4A ∴P1 = I12 R1 = 2 x 2 x 6 = 24W P2 = I22 R2 = 4 x 4 x 3 = 48W thus P1/P2 = 24/48 = 1/2 ; OR P1 : P2 = 1:2

K.E = 1/2MV2 Force, F = ma => a = F/m = 12/4 = 3ms-2 But a = (V-U) / t => V = u + at If the initial velocity U = 0, then V = at = 3 x 3 = 9ms-2 ∴ K.E, = 1/2ms-2 1/2 4 x 9 x 9 = 162J

Component of 8N along the horizontal = 8 cos 60o = 8 x 0.5 = 4N Similarity Component of 6N along the horizontal = 6 cos 60o = 3N ∴ Total force towards the right = 10 + 4 + 3 = 17N Again total force toward the left = 4N ∴ Net horizontal force (towards the right) = 17-4 = 13N

g\(_e\) = \(\frac{GM_e}{R_e^2}\) g\(_m\) = \(\frac{GM_m}{R_m^2}\) But g\(_e\) = 80 g\(_m\) R\(_e\) = 4 R\(_m\) Divide through by g\(_m\) by g\(_e\) \(\frac{g_m}{g_e}\) = \(\frac{GM_m}{R_m^2}\) \(\div\) \(\frac{GM_e}{R_e^2}\) \(\frac{g_m}{g_e}\) = \(\frac{GM_m}{R_m^2}\) x \(\frac{R_e^2}{GM_e}\) \(\frac{g_m}{g_e}\) = \(\frac{M_m}{M_e}\) x \(\frac{R_e^2}{R_m^2}\) \(\frac{g_m}{g_e}\) = \(\frac{1}{80}\) and \(\frac{R_e}{R_m}\) = 4 \(\frac{1}{80}\) = \(\frac{M_m}{M_e}\) x 4\(^2\) \(\frac{M_m}{GM_e}\) = \(\frac{1}{80}\) x \(\frac{1}{16}\) \(\frac{M_m}{GM_e}\) = 1: 1280

Sound travels fastest in a solid(metal) because the particles are closely packed and have high elasticity. This allows vibrations to pass from one atom to the next much faster than in liquids and gases, where the particles are far apart.

No expanded working has been attached for this question yet. The verified answer is Option C.

Heat supplied by the heater in 10 mins = power x time = 50 x (10 x 60) = 30000 J This heat is equal = MCΔt = 5 x c x 12 = 60cJ = 60C = 30,000 C = 30,000/60 C = 500 J kg-1K-1

Pressure = Force / Area = Weight of the man / Area of his feet => 2.8 x 103 = Weight of the man / 4 x 10-2 ∴ Weight of the man = 2.8 x 103 x 4 x 10-2 = 112N

R.d = Wt in Air-Wt in Air-Wt in water = \(\frac{60.0 - 48.2}{60.0 - 44.9}\) = 0.782

E = \(\frac{1}{2}Ke^2\) = \(\frac{1}{2} \times 200(0.8)^2 = 64J\)

M.A = \(\frac{Eff \times V.r}{100} = \frac{80 \times 5}{100} = 4\) Load = effort x M.A = 4 x 500 = 2000N

\(\Delta\)y = Vice - Vwater = \(\frac{90}{0.9} - \frac{90}{1} = 10cm^3\)

P = hpg + A.P = 5.2 x 1000 x 10 + 1.02 x 105 = 1.54 x 105