An astronaut at rest has a heart rate of 65 beats/min. What will her heart rate be as measured by an earth observer when the astronaut's spaceship goes by the earth at a speed of 0.80c?
a. 108 beats/min
c. 81 beats/min
b. 39 beats/min
d. 52 beats/min
Question 2
A ground observer measures the period of a pendulum moving as a part of an inertial frame of reference to be 2.30 s as the inertial frame moves by at a velocity of 0.800c. What would the observed period be of the same pendulum if its inertial frame were at rest with respect to the observer?
a. 3.03 s
c. 1.84 s
b. 1.38 s
d. 4.25 s