Answer: 2.61 s
Explanation:
We are given the following data:
is the initial height of the object
is the initial height of the object
In addition, the motion of the object is given by:
(1)
Where:
is the final height of the object
is the time the object is in the air before hitting the ground
Rewritting (1) with the given data:
(2)
Solving the quadratic equation with the quadratic formula
, where
,
,
and choosing the positive value of time:
(3)
(4) This is the time
Folded mountains occur when the rocks push against each other.
The thermal efficiency of a combustion system is simply
the ratio of heat out and heat in, that is:
efficiency = heat out / heat in
efficiency = 1030 J / 1540 J
efficiency = 0.669
<span>So the efficiency is 0.669</span>