Answer:
7560 Joules
Explanation:
= Mass of first car = 
= Mass of second car = 
= Initial Velocity of first car = 0.3 m/s
= Initial Velocity of second car = -0.12 m/s
v = Velocity of combined mass
As linear momentum of the system is conserved

Energy lost is

The Energy lost in the collision is 7560 Joules
In a oxidation-reduction reaction, the oxidizing agent always undergoes reduction.
TRUE.
f' = frequency observed by the police car after sound reflected from the vehicle and comes back to police car = 1250 Hz
f = frequency emitted by the police car = 1200 Hz
V = speed of sound = 340 m/s
v = speed of vehicle = ?
frequency observed by the police car is given as
f' = f (V + v)/(V - v)
inserting the values in the above equation
1250 = 1200 (340 + v)/(340 - v)
v = 6.9 m/s
Answer:
B. It is directly proportional to the source charge.
Explanation:
Gauss's law states that the total (net) flux of an electric field at points on a closed surface is directly proportional to the electric charge enclosed by that surface.
This ultimately implies that, Gauss's law relates the electric field at points on a closed surface to the net charge enclosed by that surface.
This electromagnetism law was formulated in 1835 by famous scientists known as Carl Friedrich Gauss.
Mathematically, Gauss's law is given by this formula;
ϕ = (Q/ϵ0)
Where;
ϕ is the electric flux.
Q represents the total charge in an enclosed surface.
ε0 is the electric constant.
Hence, the statement which is true of the electric field at a distance from the source charge is that it is directly proportional to the source charge.
Atomic mass= number of protons + number of neutrons

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