Answer:
See the answers below.
Explanation:
Momentum is defined as the product of mass by velocity, and can be calculated by means of the following expression.

where:
P = Momentum [kg*m/s]
m = mass = 10 [g] = 0.01 [kg]
v = velocity = 400 [m/s]
i)
![P=0.01*400\\P=4[kg*m/s]](https://tex.z-dn.net/?f=P%3D0.01%2A400%5C%5CP%3D4%5Bkg%2Am%2Fs%5D)
ii)
The momentum of the gun is equal to zero, because it does not move before being fired, the weapon only moves after having fired the weapon.

iii)
Since the momentum is conserved before and after the shot, the same momentum given to the bullet is equal to the momentum received by the gun.

![v_{recoil}=P/m\\v_{recoil}= 4/2\\v_{recoil}=2[m/s]](https://tex.z-dn.net/?f=v_%7Brecoil%7D%3DP%2Fm%5C%5Cv_%7Brecoil%7D%3D%204%2F2%5C%5Cv_%7Brecoil%7D%3D2%5Bm%2Fs%5D)
-The group 7 elements are also known as the halogens.
They include fluorine, chlorine, bromine and iodine, which all have seven
electrons in their outer shell.
-The noble gases
make a group of chemical elements with comparable properties; under standard
conditions, they are all odorless, colorless, monatomic gases with very low
chemical reactivity. The six noble gases that occur naturally are helium, neon,
argon, krypton, xenon, and the radioactive radon. FACT: They can also act like
a glow stick.<span>[ID1] </span>
<span> [ID1]</span>
Position displacement velocity acceleration are vectors and the rest are scalars
Answer:
at y=6.29 cm the charge of the two distribution will be equal.
Explanation:
Given:
linear charge density on the x-axis, 
linear charge density of the other charge distribution, 
Since both the linear charges are parallel and aligned by their centers hence we get the symmetric point along the y-axis where the electric fields will be equal.
Let the neural point be at x meters from the x-axis then the distance of that point from the y-axis will be (0.11-x) meters.
<u>we know, the electric field due to linear charge is given as:</u>

where:
linear charge density
r = radial distance from the center of wire
permittivity of free space
Therefore,





∴at y=6.29 cm the charge of the two distribution will be equal.
Answer: 9
Explanation:
Kinetic energy is the energy possessed by a moving object. It is measured in joules, and depends on the mass (m) of the object and the speed (v) by which it moves i.e K.E = 1/2 x mass x velocity^2
So, car is traveling 120 km/h
KE = 1/2x m x (120 km/h)^2
KE = 0.5 x m x 14400
KE1 = 7200m
So, car is traveling 40 km/h
KE = 1/2x m x (40 km/h)^2
KE = 0.5 x m x 1600
KE2 = 800m
Now, divide the value of kinetic energy obtained during 120 km/h by that obtained during 40 km/h
i.e 7200m / 800m
= 9
Thus, the kinetic energy will be 9 times more at a speed of 120 km/h than at 40 km/h