Answer:
option C
Explanation:
Let mass of the bullet be m and velocity be v
mass of gun be M and bullet be V
now,
using conservation of momentum for gun 1
(M+m) V' = 2 mv + 3 MV
V' = 0
3 M V = - 2 mv
momentum of gun 1 =- 2 mv---------(1)
now for gun 2
(M+m) V' = mv + MV
V' = 0
M V = - mv
momentum of gun 1 = -mv-----------(2)
dividing equation (1) by (2)


the correct answer is option C
Answer:
D; The microscope and magnifying glass block out the light, which allows the naked eye to focus on the object.
Explanation:
This is to prevent chromatic abberation
Given Information:
Current in loop = I = 62 A
Magnitude of magnetic field = B = 1.20x10⁻⁴ T
Required Information:
Radius of the circular loop = r = ?
Answer:
Radius of the circular loop = 0.324 m
Explanation:
In a circular loop of wire with radius r and carrying a current I induces a magnetic field B which is given by
B = μ₀I/2r
Please note that for an infinitely straight long wire we use 2πr whereas for circular loop we use 2r
Where μ₀= 4πx10⁻⁷ is the permeability of free space
Re-arranging the equation yields
r = μ₀I/2B
r = 4πx10⁻⁷*62/2*1.20x10⁻⁴
r = 0.324 m
Therefore, the radius of this circular loop is 0.324 m
Answer:
C)Before leaving for their trip, turn the central heating system off, along with lights and electrical household appliances.
Explanation:
Although, the other three options will also reduce their electricity bill but they do not explain why Mr. Hernandez's family got same electricity bill as last year even though this time they were not home for one and a half week. Also, A), B) and D) ideas are not reasonable.
So, the only conclusion is that even when they were on a vacation. the electrical appliances in their home were on. That's why the bill remained the same.
The idea of turning the central heating system off, along with lights and electrical household appliances before they leave for the trip will help reduce the energy usage. Also, it is reasonable.