DP Physics (last assessment 2024)
Question 17N.3.HL.TZ0.b
Date | November 2017 | Marks available | [Maximum mark: 2] | Reference code | 17N.3.HL.TZ0.b |
Level | HL | Paper | 3 | Time zone | TZ0 |
Command term | Calculate | Question number | b | Adapted from | N/A |
b.
[Maximum mark: 2]
17N.3.HL.TZ0.b
The Schwarzschild radius of a black hole is 6.0 x 105 m. A rocket is 7.0 x 108 m from the black hole and has a clock. The proper time interval between the ticks of the clock on the rocket is 1.0 s. These ticks are transmitted to a distant observer in a region free of gravitational fields.
Calculate the number of ticks detected in 10 ks by the distant observer.
[2]
Markscheme
ALTERNATIVE 1 (10 ks is in observer frame):
Δt' =
9995.7 so 9995 «ticks»
Allow 9996
Allow ECF if 10 is used instead of 10000
ALTERNATIVE 2 (10 ks is in rocket frame):
Δt =
10004 «ticks»
Allow ECF if 10 is used instead of 10000
