# Thread: Applied math questions

1. ## Applied math questions

Ive recently started studying and ive been having some trouble with two problems in my A-Math class. If anyone knows the answer or could give me some tips on how to solve it I would greatly appreciate it.
1. A ball rolls under gravity inside a smooth bowl with circular cross
section and inner radius
a. Show that the ball can roll in a horizontal

circle at a height
h above the bottom of the bowl provided

v^2
= gh(2a h/a h).

2. A force
F i ˆj + ˆk acts at the point (1, 3,2).
(a) Find the moment of
F about the origin.
(b) Find the moment of
F about the point at (0, 1,1).

Thanks
Totster.

2. 1. the normal reaction on the ball has 2 components, horizontal and vertical.

the horizontal is the centriptal force that makes the ball move in a circle
the vertical must be equal to the gravitational force so the balls doesnt change height

to solve the problem you need to find the horizontal component and then use trigonometry to find the vertical and equate it to g.

2. the moment is given by M=r x F