Practically yes
So
If mass is more output may come less so it affects the efficiency practically
But thepritically it doesn't
' +4 m/s² ' means that the pigeon's speed is 4 m/s greater every second.
Starting from zero speed, after 10 seconds, its speed is
(10 x 4m/s) = 40 m/s.
We can't say anything about its velocity, because we have
no information regarding the direction of its flight.
Elastic potential energy.
When you stretch a rubber band it has the "potential" to do work, to fly in a given direction. In doing so it changes it's elastic potential energy to kinetic energy.
Impulse describes the change of momentum. Since we don't know the momentum of the soccer ball before the hit, this question is hard to answer. If you assume the momentum of the ball before the hit was p = 0, then the change in momentum is just Δp = Impulse = mv.
Answer:
Option (B) is correct.
Explanation:
Given that the molecules of hydrogen gas (
) react with molecules of oxygen gas (
) in a sealed reaction chamber to produce water (
).
The governing equation for the reaction is

From the given, the only fact that can be observed that 2 moles of
and 1 mole of
reacts to produce 2 moles of
.
As the mass of 1 mole of
grams ... (i)
The mass of 1 mole of
grams ...(ii)
The mass of 1 mole of
grams (iii)
Now, the mass of the reactant = Mass of 2 moles of
+ mass 1 mole of 
[ using equations (i) and (ii)]
grams.
Mass of the product = Mass of 2 moles of 
[ using equations (iii)]
=36 grams
As the mass of reactants = mass of the product.
So, mass is conserved.
Hence, option (B) is correct.