Answer:
a) 3673469.39 seconds
b) 6.61×10¹⁴ m
Explanation:
t = Time taken
u = Initial velocity
v = Final velocity = 0.12×3×10⁸ m/s
s = Displacement
a = Acceleration due to gravity = 9.8 m/s²
Equation of motion

Time taken to reach 12% of light speed is 3673469.39 seconds

The distance it would have to travel is 6.61×10¹⁴ m
= 3.456 × 1011
(scientific notation)
= 3.456e11
(scientific e notation)
= 345.6 × 109
(engineering notation)
(billion; prefix giga- (G))
= 345600000000
(real number)
Explanation:
6a) Work = force × distance
W = Fd
W = (60 N) (10 m)
W = 600 J
6b) Change in energy = work
ΔKE = 600 J
7a) Kinetic energy is half the mass times the square of the velocity.
KE = ½ mv²
KE = ½ (0.4 kg) (25 m/s)²
KE = 125 J
7b) Work = change in energy. When the ball is stopped, it has zero kinetic energy.
W = ΔKE
W = 0 J − 125 J
W = -125 J
Answer:
(a) B = 2.85 ×
Tesla
(b) I = I = 0.285 A
Explanation:
a. The strength of magnetic field, B, in a solenoid is determined by;
r = 
⇒ B = 
Where: r is the radius, m is the mass of the electron, v is its velocity, q is the charge on the electron and B is the magnetic field
B = 
= 
B = 2.85 ×
Tesla
b. Given that; N/L = 25 turns per centimetre, then the current, I, can be determined by;
B = μ I N/L
⇒ I = B ÷ μN/L
where B is the magnetic field, μ is the permeability of free space = 4.0 ×
Tm/A, N/L is the number of turns per length.
I = B ÷ μN/L
= 
I = 0.285 A