Answer: 0.5 seconds or 2.625 seconds
Explanation:
At t = 0, The ball is 4 ft above the ground.
The height of the football varies with time in the following way:
s(t) = -16 t² + 50 t + 4
we need to find the time in which the height would of the football would be 25 ft:
⇒25 = -16 t² + 50 t + 4
we need to solve the quadratic equation:
⇒ 16 t² - 50 t + 21 = 0

⇒ t = 0.5 s or 2.625 s
Therefore, at t = 0.5 s or 2.625 s, the football would be 25 ft above the ground.
Atomic disguise makes helium look like hydrogen. ... A helium atom consists of a nucleus containing two positively charged protons and two neutrons, encircled by two orbiting electrons which carry a negative charge. A hydrogen atom has just one proton and one electron
Explanation:
Mass of the crate, m = 68 kg
We need to find the resulting acceleration if :
(a) Force, P = 0
P = m a
⇒ a = 0
(b) P = 181 N



(c) P = 352 N



Hence, this is the required solution.
Answer:

Explanation:
According to question,
Charge 1 and charge 2 are 
The distance between charges is 2 m
We need to find the force with which two positive charges repel. It is called electrostatic force of repulsion. It can be given by :

So, the electric force of repulsion is
.