Answer:
45.13 beats/min
Explanation:
Speed of space vehicle = 0.51c
the pulse rate measured by the astronaut= 61.0 beats per minute
Pulse rate measured by the Earth observer is given by
[tex]=(pulse\ rate)\sqrt{1-\frac{v^2}{c^2} }[/tex]
putting vales we get
[tex]=61\sqrt{1-\frac{0.51^2c^2}{c^2} }[/tex]
= 45.13 beats/min