French Assassins
A stealthy assassin climbs all 301m of the Eiffel Tower.
He wants to know how long it will take for a large stone to reach his target below.
He aims for a headshot of the 2m giant.
Calculate the time between dropping the stone and impact.
Take g as 9.81ms-2 and exclude air resistance and cross winds!
Give answer in seconds (1dp).
The answer is 7.8.
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1 solution
We know from basic equations of kinematics,
d(distance travelled)=u(initial velocity).t+ 1/2 gt^2………………(1)
As the stone is dropped,there is no initial velocity,u=0 Therefore,equation (1) reduces to d=1/2gt^2……………(2)
d=(301-2)m=299m Putting the values and solving equation (1),we get,t=7.8