Answer:
86.4 m horizontal from landing spot
Explanation:
Find out how long before the ball hits the ground
vertical speed of ball = -2 m/s gravity = - 9.81 m/s^2
find time to hit ground from 100 m
( height will be<u> zero</u> when it hits the ground)
<u>0 </u>= 100 - 2 t - 1/2 ( 9.81) t^2
use Quadratic Formula to find t = 4.32 seconds
horizontal speed of ball = 20 m/s
in 4.32 seconds it will travel horizontally 20 m/s * 4.32 s = 86.4 m
Answer:

Explanation:
The change in kinetic energy will be simply the difference between the final and initial kinetic energies: 
We know that the formula for the kinetic energy for an object is:

where <em>m </em>is the mass of the object and <em>v</em> its velocity.
For our case then we have:

Which for our values is:

The gravitational force.
In fact, the motion of the projectile is composed by two independent motions:
- on the horizontal direction, it is a uniform motion (with constant speed)
- on the vertical direction, it is a uniformly accelerated motion, where the vertical acceleration g is given by the gravity exerted by the Earth on the projectile.
For this reason, the composition of the two motions results in a parabolic trajectory.
Answer:
0.12959085 J
Explanation:
k = Coulomb constant = 
q = Charge = 1.55 μC
d = Distance between charge = 0.5 m
Electric potential energy is given by

In this system with three charges which are equidistant from each other


The potential energy of the system is 0.12959085 J