Answer:
B) 1.2 N, toward the center of the circle
Explanation:
The circumference of the circle is:
C = 2πr
C = 2π (0.70 m)
C = 4.40 m
So the velocity of the ball is:
v = C/t
v = 4.40 m / 0.60 s
v = 7.33 m/s
Sum of the forces in the radial direction:
∑F = ma
T = m v² / r
T = (0.015 kg) (7.33 m/s)² / (0.70 m)
T = 1.2 N
The tension force is 1.2 N towards the center of the circle.
The north Celestial pole is 42.036 degrees above the northern horizon when I look at it from my front yard.
I don't need to know my latitude to discover that, since I can measure it directly in the sky.
But when I DO look up my latitude, it blows my mind ! It's the exact same number ... 42.036 degrees north ! This can't be just a coincidence. There must be some connection !
(YOU can't use this number. It's different where you live.)