Question

A car with fuzzy dice hanging from the rear view mirror by a single string drives along at a
constant 25.0 m/s. a) If the dice have a mass of 0.030 kg, what is the angle of the string (relative to
vertical)? b) What is the tension in the string? c) As the driver takes a turn with a radius of 150.0 m,
what will the angle then be? (at same speed) d) What is the tension in the string during this turn?

Answer 1

(a) v=const, a=0 =>α =0,
(b)T=m•g.
(c)
m•v² /R=T•sin α,
m•g=T•cos α.
m•v²/R•m•g=T•sin α/T• cos α.
v²/R •g = tan α.
α =arctan(v²/R •g).
(d)
T=mg/cosα