Question

80 railway wagons all of same mass 5 × 10³ kg are pulled by an engine with a force of 4 × 10⁵ N. The tension in the coupling between 30^th and 31^st wagon from the engine is –

• A. 25 × 10⁴ N
• B. 20 × 10⁴ N
• C. 32 × 10⁴ N
• D. 40 × 10⁴ N

Answer 1

Answer: (A)

25 × 10⁴ N

Answer 2

According to train,

a = $\frac{4 \times 10^{5}}{80 \times 5 \times 10^{3}}$ = 1 m/s²

Thus, tension between 30^th and 31^st wagon is

T = ma = 50 × 5 × 10³ × 1

= 25 × 10⁴ N