n a race to the moon, by 3/4ths the distance, light is one or ten meters ahead of the particle.  We routinely approximate mass as zero, gamma as infinite, and speed as the speed of light.  ("Massless particles" -- gamma and m have to be eliminated from the expressions.  Light is a true massless particle.) If a massless particle has momentum 1,349 MeV/c, calculate its energy in MeV.

Consider a proton that has a momentum of 1.00 kg·m/s.  Part (a)  Calculate the relativistic parameter γ for the proton. You will have to use a 2.998 × 108 for the speed of light to get this answer correct.  Part (b)  What is its speed, in meters per second? Such protons form a rare component of cosmic radiation with uncertain origins.

Suppose a cosmic ray colliding with a nucleus in the Earth's upper atmosphere produces a muon that has speed v = 0.99c. The muon then travels at constant speed and lives 1.5 μs as measured in the muon's frame of reference. (You can imagine this as the muon's internal clock.)Randomized Variablesv = 0.99 ct = 1.5 μs   Part (a)  How many kilometers does the muon travel according to an Earth-bound observer?  Part (b)  How many kilometers of the Earth pass by as viewed by an observer moving with the muon? Base your calculation on its speed relative to the Earth and its lifetime (proper time).

The mean lifetime of mesons (pions) is 26 ns. A beam of pions is travelling at 0.93c. As measured in the laboratory: a) What is their mean lifetime? b) How far would they travel before they decay?

The "muon" is an unstable particle with rest mass m = 106 MeV/c^2. The mean lifetime of a muon at rest is 2.2 microseconds. (micro= 10^-6) Now consider a muon moving in a laboratory, with total relativistic energy E = 2.5 GeV. (G= giga = 10^9). What is the mean distance that the muon would travel relative to the lab, before decaying? (in m) OA: 5.098x103 OB: 7.392x103 OC: OD: OE: 1.072x104 1.554x104 2.254x104 OF: 3.268x104 OG: 4.738x104 OH: 6.870x104

Mass of a proton: 1.007825 u; Mass of a neutron: 1.008665 u 1 The lifetime of a free neutron is 887 s. If a neutron moves with a speed 2.9 × 108 m/s relative to an observer in the lab, what does the observer measure the neutron's lifetime to be? What is this an example of? 2. (a) What is the rest energy (in joules) of a subatomic particle whose (rest) mass is 6.7 x 10-3¹ kg? (b) How many MeV's of energy is this? 3. The rest energy of a particular subatomic particle is 1200 MeV. If this particle is traveling at 90% the speed of light, what is its total relativistic energy?

If relativistic effects are to be less than 1%, then the dimensionless parameter γ must be less than 1.01. At what velocity, in terms of c, is γ = 1.01?

The velocity of an alpha particle, He2+, with a mass of 6.64×10−27kg changes from v1=(−0.30, 0.45,0.10)c to v2=(−0.50, 0.30, −0.75)c, where c=3×108m/s. Determine the change in the particle’s kinetic energy.(In the kinetic energy formula, do not forget to square the speed of light.)