alleryA train brakes from 30 m/s to rest in 15 seconds. If the mass of the train is 20,000 kg, the BRAKING FORCE is:
A40,000 N
B60,000 N
C30,000 N
D20,000 N
Answer & Solution
Correct answer: A. 40,000 N
Acceleration (deceleration) a = (0 − 30) / 15 = −2 m/s².
Force F = ma = 20,000 × (−2) = −40,000 N. The negative sign indicates braking force (opposite to motion).
Magnitude is 40,000 N (about the weight of 4 tonnes).
Keep practising Force and Laws of Motion
Browse all Force and Laws of Motion questions for CBSE Class 9, or explore more Science topics.
Related questions
Match each practical sport/safety mechanism with its physics principle:Match each dynamic concept with its definition:Match each type of inertia with its daily life illustration:Match each of Newton's Laws of Motion with its core statement:Pick the right answer, quicklySpot the one that does not fitBalanced or unbalanced force?Order the story of a braking car