An amusement park ride consists of a car moving in a vertical circle on the end of a rigid boom of negligible mass. The combined weight of the car and riders is $5.0 \mathrm{kN},$ and the circle's radius is $10 \mathrm{~m} .$ At the top of the circle, what are the (a) magnitude $F_{B}$ and $(\mathrm{b})$ direction (up or down) of the force on the car from the boom if the car's speed is $v=5.0 \mathrm{~m} / \mathrm{s} ?$ What are
(c) $F_{B}$ and
(d) the direction if $v=12 \mathrm{~m} / \mathrm{s} ?$