Question

A paper weight is dropped from the roof of a block of multi story flats. Each storey being 3 metre high. It passes the ceiling of the 20th storeys at 30m/sec. If g=10m/s2, how many storeys does the flat have?

Answer 1

Answer:35

Explanation:

u=0, v=30, a=g=10

applying the formula v2-u2=2as ,

s=45m

as each storey being 3m high ,

45/3 = 15 storeys

so, 20 + 15 = 35 storeys

Answer 2

Answer:

set third equation of motion