一道英文物理题哦A ball of mass m is attached to a string of length L

一道英文物理题哦
A ball of mass m is attached to a string of length L .
It is swung in a vertical circle with enough speed to keep the
string taut throughout the motion. Assume the ball travels
freely in the circle with negligible loss of mechanical energy.
Determine if the following six statements are true or false;
e.g., enter 输入TTFFFF.
i) mvt
2 /L = Tt−mg , where vt and Tt are the speed of the
ball and the tension of the string at the top of the circle.
ii) The speed of the ball at the bottom of the circle is greater
than the speed at the top of the circle.
iii) The tension in the string is less at the top of the circle than
at the bottom of the circle.
iv) The difference between the tensions at the top and at the
bottom of the circle depends on the average speed of the
ball.
v) The acceleration of the ball at the top of the circle is di-
rected ‘down’.
vi) The tension in the string at the top of the circle is always
greater than the weight of the ball.
Assume that m = 0.40 kg and L = 1.65m. What
is the difference in tension, Tb−Tt , between when the ball is
at the bottom and when it is at the top?