6 Markers

Question 1

Muons are produced at a height of 10km in the atmosphere. The velocity of the muons is 0.99c. The average lifetime for muons is normally 2.2us and get muons are produced in the upper atmosphere and are found in significant numbers at sea level. Discuss this apparent anomaly.

Answer 1

• v = d/t
• time = 3x10^-5s
• compares with lifetime which is 15 times smaller
• relativistic speeds of muon
• time dilation occurs
• so muon lifetime increases