Given Information:
Mass of electron = m = 9x10⁻³¹ kg
initial speed of electron = v₁ = 0.92c
Force = F = 1.4x10⁻¹³ J
Distance = d = 3 m
Required Information:
Final speed of electron = v₂ = ?
Answer:
Final speed of electron = v₂ = 2.974x10⁸ m/s
Explanation:
As we know from the conservation of energy,
E₂ - E₁ = W
E₂ = E₁ + W
Where E₂ is the final energy of electron and E₁ is the initial energy of electron
The above equation can be written in the form of particle energy
γ₂mc² = γ₁mc² + W
where γ₁ and γ₂ are given by
γ₁ = 1/√1 - (v₁/c)²
γ₂ = 1/√1 - (v₂/c)²
First calculate γ₁
γ₁ = 1/√1 - (0.92c/c)²
γ₁ = 2.55 m
Now calculate γ₂
γ₂ = (γ₁mc² + W)/mc²
First we need to find the work done
W = F*d
W = 1.4x10⁻¹³*3
W = 4.2x10⁻¹³ J
so γ₂ is
γ₂ = (2.55*9x10⁻³¹*(3x10⁸)² + 4.2x10⁻¹³)/9x10⁻³¹*(3x10⁸)²
γ₂ = 7.73
Now we can find the new speed of the electron
γ₂ = 1/√1 - (v₂/c)²
Re-arranging the above equation results in
v₂ = c*√(1 - 1/γ₂²)
v₂ = 3x10⁸*√(1 - 1/7.73²)
v₂ = 2.974x10⁸ m/s
<span>The scientists use data
and measurement to obtain empirical evidence. Data can be collected through
direct observation or else experimentation. Empirical measurements and data can
be gathered by using qualitative and quantitative methods. Empirical evidence
contains the recording and analyzing the data which is a central part of scientific
method.</span>
Answer:
A. F=107.6nN
B. Repulsive
Explanation:
According to coulombs law, the force between two charges is express as
F=(Kq1q2) /r^2
If the charges are of similar charge the force will be repulsive and if they are dislike charges, force will be attractive.
Note the constant K has a value 9*10^9
Hence for a charge q1=7.10nC=7.10*10^-9, q2=4.42*10^-9 and the distance r=1.62m
If we substitute values we have
F=[(9×10^9) ×(7.10×10^-9) ×(4.42×10^-9)] /(1.62^2)
F=(282.4×10^-9)/2.6244
F=107.6×10^-9N
F=107.6nN
B. Since the charges are both positive, the force is repulsive
If there are two bulbs in series, and each bulb has
resistance = 3 ohms,
then their total resistance in series is 6 ohms.
When the series pair of bulbs is connected across the terminals
of the battery, the current through the circuit is
Current = (voltage) / (resistance)
= (12 volts) / (6 ohms) = 2 amperes
