Answer:
a = 1600 m / s²
Explanation:
For this exercise we use the kinematics relations,
v² = v₀² + 2 a x
where v₀ is the initial velocity of the bullet, which as part of rest is zero, for the distance (x) we can assume that the gases accelerate along the entire trajectory of the cannon x = 2m
a = 
let's calculate
a = 
a = 1600 m / s²
The correct answer is:
Work is negative, the environment did work on the object, and the energy of the system decreases.
In fact, the work-energy theorem states that the work done by the system is equal to its variation of kinetic energy:
In this problem, the variation of kinetic energy 
is negative (because the final velocity is less than the initial velocity), so the work is negative, and this means that the environment did work on the object, and its energy decreased.
Answer of your question is in this photo
You should just ask the wave
Neither of those questions makes sense, and I believe that you should not waste your time worrying about them.
#61 gives you a lot of information about a ball, and then asks a question about a glove.
#62 gives a mysterious equation, doesn't tell you what either of the variables represents, and then asks for a quantity without ever telling us how that quantity is related to the equation.
Personally, my response to both questions would be "Insufficient information given".
