6.022*10^23 atoms/mole of reactant
(this is chemistry not physics)
Answer:
v = 19.6 m/s
Explanation:
Height of building = 30.6 m.
Height of window from the ground level= 10.7 m.
Acceleration due to gravity = 9.8
At initial condition ball at rest condition so u= 0 m/s.
Lets take when passes through the window ,velocity is v.
Here acceleration is constant so we can apply motion equation .
We know that
v= u + a t
So by putting the values
v = 0 +9.8 x 2
v = 19.6 m/s
So the velocity of ball is 19.6 m/s when passes through the window after 2 s.
Answer:
32%
Explanation:
For a heat engine, efficiency is work out divided by heat in:
η = Wₒ / Qᵢ
Since energy is balanced, heat in is the sum of work out and heat out:
Qᵢ = Wₒ + Qₒ
Therefore:
η = Wₒ / (Wₒ + Qₒ)
Given Wₒ = 710 J and Qₒ = 1480 J:
η = 710 / (710 + 1480)
η = 0.32
The thermal efficiency is 32%.