According to the conservation of mechanical energy, the kinetic energy just before the ball strikes the ground is equal to the potential energy just before it fell.
Therefore, we can say KE = PE
We know that PE = m·g·h
Which means KE = m·g·h
We can solve for h:
h = KE / m·g
= 20 / (0.15 · 9.8)
= 13.6m
The correct answer is: the ball has fallen from a height of 13.6m.
Answer:
multiply the number of moles of Na by the conversion factor 6.02214179×1023 atoms Na/ 1 mol Na, with 6.02214179×1023 atoms being the number of atoms in one mole of Na (Avogadro's constant), which then allows the cancelation of moles, leaving the number of atoms of Na.
I think Y is the answer to number 4
Answer:
9.01amp
Explanation:
Power = V^2/R
Given that v = 11volts, P = 99watts
99 = 11^2/R
11×11 = 99R
121= 99R
R = 121/99
R= 1.22ohms
From ohms Law; V = IR
11volts = I × 1.22ohms
I = 11/1.23
I = 9.01 amp
Explanation:
The newton's laws of motion are:
First law:
"A body will remain in its state of rest or of uniform motion along a path unless it is acted upon by an external force. ".
This is popularly called the law of inertia.
Second law:
"the acceleration of a body is produced by a net force that is inversely proportional to the mass of the body".
Third law:
"action and reaction forces are equal and opposite in direction".
learn more:
Newton's laws brainly.com/question/11411375
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