I assume that the ball is stationary (v=0) at point B, so its total energy is just potential energy, and it is equal to 7.35 J.
At point A, all this energy has converted into kinetic energy, which is:
And since K=7.35 J, we can find the velocity, v:
Titty milk I think because it taste amazing so you can go 21km/h
The kinetic energy of the electron is
where
is the mass of the electron and v its speed. Since we know the value of the kinetic energy,
, we can find the value of the speed v:
Answer:
B. posititvely charged particles
Explanation:
Opposites attract to each other, and the same charge repels.
Consider the upward direction of motion as positive and downward direction of motion as negative.
a = acceleration due to gravity in downward direction = - 9.8 
v₀ = initial velocity of rock in upward direction = ?
v = final velocity of rock at the highest point = 0 
t = time to reach the maximum height = 4.2 sec
Using the kinematics equation
v = v₀ + a t
inserting the values
0 = v₀ + (- 9.8) (4.2)
v₀ = 41.2
