Question

when a bus suddenly starts moving forward the passenger in the bus Falls backward why

Answer 1

when the bus is at rest the upper part and lower of the passengers is in rest .when a bus suddenly starts the lower part of the body of the passengers comes in motion but the upper part continues to be in rest. due to this inertia of rest

Answer 2

When we are sitting in a bus both our body and the bus are at rest.
When the bus accelerates from rest, the lower part of the body comes in motion, with the bus.
The upper part of the body continues to be in its state of inertia of rest and thus we fall backward...
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