One strategy in a snowball fight is to throw a snowball at a high angle over level ground. While your opponent is watching this first snowball, you throw a second snowball at a low angle and time it to arrive at the same time as the first. Assume both snowballs are thrown with the same initial speed 20.5 m/s. The first snowball is thrown at an angle of 68◦ above the horizontal. At what angle should you throw the second snowball to make it hit the same point as the first? The acceleration of gravity is 9.8 m/s 2 . Answer in units of ◦ .

Several people stand on a bridge over a river.  The bridge is not level, so the people are all different heights above the river.  Each person throws a stone to the river. a) The first person is 26.8 m above the river and throws her stone with a speed of 16.6 m/s at an angle of 6 degrees to the horizontal (positive degrees are above horizontal, negative degrees are below).  How long does it take her stone to hit the water, in seconds? b) The second person is 19.0 m above the river and throws his stone with a speed of 17.1 m/s at an angle of -21.4 degrees to the horizontal (positive degrees are above horizontal, negative degrees are below).  What is the range of his stone, in meters? c)The third person is 9.1 m above the river and throws their stone with a speed of 6.5 m/s at an angle of 9.3 degrees to the horizontal (positive degrees are above horizontal, negative degrees are below).  What is the speed of this stone (in m/s) just before it strikes the river?

Initially, a particle is moving at 5.45 m/s at an angle of 38.5 above the horizontal. Four seconds later, its velocity is 6.24 m/s at an angle of 54.3 below the horizontal. What was the particle's average acceleration during these 4.00 seconds in the x-direction (enter first) and the y-direction?

An object is located initially at an origin. It has acceleration 3.00 m/s2, 90° and velocity 5.00 m/s, 0°. Determine the position (x, y) and the velocity (magnitude and direction) for times 1.00 s, 2.00 s and 3.00 s. Graph the position on an x-y coordinate plane for these times. Include the velocities and acceleration.