Answer:
a) 3.43 m/s
Explanation:
Due to the law of conservation of momentum, the total momentum of the bullet - rifle system must be conserved.
The total momentum before the bullet is shot is zero, because they are both at rest, so:

Instead the total momentum of the system after the shot is:

where:
m = 0.006 kg is the mass of the bullet
M = 1.4 kg is the mass of the rifle
v = 800 m/s is the velocity of the bullet
V is the recoil velocity of the rifle
The total momentum is conserved, therefore we can write:

Which means:

Solving for V, we can find the recoil velocity of the rifle:

where the negative sign indicates that the velocity is opposite to direction of the bullet: so the recoil speed is
a) 3.43 m/s
Answer:
From the previous explanation Student No. 1 has the correct explanation
Explanation:
When the fluorescent lamp emits a light it has the shape of its emission spectrum, this light collides with the atoms of Nitrogen and excites it, so these wavelengths disappear, lacking in the spectrum seen by the observed, for which we would see an absorption spectrum
The nitrogen that was exited after a short time is given away in its emission lines, in general there are many lines, so the excitation energy is divided between the different emission lines, which must be weak
From the previous explanation Student No. 1 has the correct explanation
Answer:
10.6cm
Explanation:
We are given 5.3cm below the starting point (spring extension).
Therefore, to find static vertical equilibrium, we use the equation:
kx = mg
Where:
k = spring constant =
=mg/5.3 kg/s²
We are told the object was dropped from rest.
Therefore:
loss in potential energy = gain in spring p.e
Let's use the expression:
mgx = ½kx²
We are asked to find the stretch at maximum elongation x.
To find x, we make x subject of the formula.
Therefore, we have:
x = 2mg/k (after rearranging the equation above)
x = (2mg) / (mg/5.3)
x = 10.6cm
Answer:
A. Adjusts how far down the piston travels
Explanation:
This type of engine changes the possition of the piston in order to modify the compression chamber volume and therefore the compression ratio of the engine. The volume of the chamber is proportional to the run of the piston (how far down the piston travels)
This engine is used to achive the optimal compression rate in each individual stage.
Answer:
A, C
Explanation:
It can be found in objects like a swing. It creates kinetic energy when it is coming back or going away, while moving.