The power required for an engine to maintain a constant speed of $50 \mathrm{~m} \mathrm{~s}^{-1}$ for a train of mass $3 \times 10^6 \mathrm{~kg}$ on rough rails is (The coefficient of kinetic friction between the rails and wheels of the train is 0.05 and acceleration due to gravity $=10 \mathrm{~m} \mathrm{~s}^{-2}$ )

• Correct answer
  A

  75 MW
• B

  40 MW
• C

  75 kW
• D

  65 MW

Hence, the correct answer is option: 'A'.