The specific latent heat of fusion of ice is 336 kJ/kg. The heat required to melt 2 kg of ice at 0°C is: MCQ with Answer and Explanation

Explanation:
I = E/(R+r) = 2/(3.5+0.5) = 2/4 = 0.5 A. Terminal V = IR = 0.5×3.5 = 1.75 V. Or E - Ir = 2 - 0.5×0.5 = 1.75 V.

Explanation:
J. J. Thomson discovered the electron in 1897 through cathode ray tube experiments, measuring charge-to-mass ratio (e/m) of cathode rays. Proton: Rutherford; neutron: Chadwick; nucleus: Rutherford's gold foil experiment. Memory aid: 'Thomson = plum pudding model (electrons in positive sphere)'. This historical question tests knowledge of subatomic particle discoveries, frequently examined in competitive exams. Always recall the experimental methods: Thomson (cathode rays), Millikan (oil drop for e), Rutherford (alpha scattering).

Explanation:
d = (v×t)/2 = (340×0.5)/2 = 170/2 = 85 m. Minimum distance for echo perception is about 17 m. Remember divide by 2 for one-way distance.