Answer:
Velocity (magnitude) is 98.37 m/s
Explanation:
We use the vertical component of the initial velocity, which is:
Using kinematics expression of vertical velocity (in y direction) for an accelerated motion (constant acceleration, which is gravity):
Now we need to find 
as a function of 
. We use the horizontal velocity, which is always the same as follow:
We know the angle at 3 seconds:
Substitute 
in 
and then solve for
With this expression we go back to the kinematic equation and solve it for initial speed
For number one the answer is Iodine because it is in the same group as fluorine. For number two the answer is Germanium for the same reason. For number three the answer is Aluminum for the same reason.
Answer:
FALSE
Explanation:
Velocity = speed with direction.
Think of speed and direction like rockets and missiles. Rockets are not smart. Missiles are smart. Rockets go in one direction. Missiles can track their targets, they have a specific destination, a specific direction.
Velocity is often used in physics, because its almost useless to know how fast an object is going if you don't know which direction it is going.
Think of it like this. If the Weather man told you a hurricane was traveling at 30 miles an hour, but didn't tell you which direction it was going, you would have no idea where to run, or if it was going to hit you at all. However, if he told you it was going 30 miles an hour to the North, and you were West of it, you would be fine, and wouldn't have to worry.
