120 km / 60 min
2 km / 1 min
1 km / 30 sec
0.5 km / 15 sec
0.03333 km / sec
0.03333 km = 33.33 m
Given Information:
Radius = r = 0.5 m
Magnetic field = 1.0 T
Required Information:
Period = T = ?
Speed = v = ?
Kinetic energy = KE = ?
Answer:
Period = 0.13x10⁻⁶ seconds
speed = 24.16x10⁶ m/s
Kinetic energy = 12.11 MeV
Explanation:
(a) period
The time period of alpha particle is related to its orbital speed as
T = 2πr/v eq. 1
According to newton's law
F = ma
Force due to magnetic field is given by
F = qvB
qvB = ma
qvB = m(v²/r)
qB = mv/r
v = qBr/m eq. 2
substitute the eq. 2 in eq. 1
T = 2πr/qBr/m
r cancels out
T = 2π/qB/m
T = 2πm/qB
T = 2π*6.65x10⁻²⁷/2*1.602x10⁻¹⁹*1
T = 0.13x10⁻⁶ seconds
(b) speed
From equation 1
T = 2πr/v
v = 2πr/T
v = 2π*0.5/0.13x10⁻⁶
v = 24.16x10⁶ m/s
(c) kinetic energy (in electron volts)
Kinetic energy is given by
KE = 0.5mv²
KE = 0.5*6.65x10⁻²⁷*(24.16x10⁶)²
KE = 1.94x10⁻¹² J
since 1 electron volt has 1.602x10⁻¹⁹ J
KE = 1.94x10⁻¹²/1.602x10⁻¹⁹
KE = 12.11 MeV
(C)
Explanation:
The circle has a radius r = 0.5 m, which means that its circumference C is

One revolution means that the stopper travels a distance equal to the circumference of the circle so the velocity of the stopper is

Answer:
Christian Doppler
Explanation:
The Scientist with the most significant contribution to the discovery of planets around other stars is Christian Doppler and his work that made this discovery possible is the Principle of DOPPLER EFFECT
<em>Christian Doppler was an Austrian scientist and physicist whose principle Doppler effect explained how observed frequency of light and sound waves are affected by a relative motion of both the source and detector </em>