One strategy in a snowball fight is to throw a snowball at a high angle over level ground. While your opponent is watching the first one, a second snowball is thrown at a low angle timed to arrive before or at the same time as the first one. Assume both snowballs are thrown with a speed of 10.0 m/s. The first one is thrown at an angle of 65.0° with respect to the horizontal.

Question

How many seconds later should the second snowball be thrown after the first to arrive at the same time?

Answer 1

To arrive at the same PLACE, the second snowball must be launched at a complementary angle of 25 degrees.

The difference in the time of flight for those two launch angles is the required delay time, Tdelay.

Tdelay = 2 (Vsin65 - Vsin25)/g
= [(10 m/s)/9.8 m/s^2]*(0.4836)
= 0.49 seconds

Answer 2

A particular Ferris wheel (a rigid wheel rotating in a vertical plane about a horizontal axis) at a local carnival has a radius of 20.0 m and it completes 1 revolution in 9.84 seconds.
(a) What is the speed (m/s) of a point on the edge of the wheel?
Using the coordinate system shown, �nd:
the (b) x component of the acceleration of point A at the top of
the wheel.
the (c) y component of the acceleration of point A at the top of the wheel
the (d) x component of the acceleration of point B at the bottom of the wheel.
the (e) y component of the acceleration of point B at the bottom of the wheel
the (f) x component of the acceleration of point C on the edge of the wheel.
the (g) y component of the acceleration of point C on the edge of the wheel