Answer:
Explanation:
The pingpong ball reaches the ground directly under the student. That means net displacement is zero
Time of fall t = 
Initial horizontal velocity = v ,
horizontal acceleration = - a ( deceleration because net displacement is zero)
0 = ut - 1/2 a t²
0 = 
v = 1/2 a 
h = 
Answer:
v = R w
With this expression we see that for each point at different radius the tangential velocity is different
Explanation:
They indicate that the angular velocity is constant, that is
w = dθ / dt
Where θ is the radius swept angle and t the time taken.
The tangential velocity is linear or
v = dx / dt
Where x is the distance traveled in time (t)
In the definition of radians
θ = s / R
Where s is the arc traveled and R the radius vector from the pivot point, if the angle is small the arc (s) and the length (x) are almost equal
θ = x / R
We substitute in the speed equation
v = d (θ R) / dt
The radius is a constant for each point
v = R dθ / dt
v = R w
With this expression we see that for each point at different radius the tangential velocity is different
Creating new elements in order to study their properties is definitely pure research.
It has no earthly [known] application, since the elements don't even exist, whereas
for each of the other choices, you've stated the desired application as the reason
for the search.
28J because mechanical energy is the sum of the potential energy and kinetic energy
