Answer:
v = 12.52 [m/s]
Explanation:
To solve this problem we must use the energy conservation theorem. Which tells us that potential energy is transformed into kinetic energy or vice versa. This is more clearly as the potential energy decreases the kinetic energy increases.
Ep = Ek
where:
Ep = potential energy [J] (units of joules]
Ek = kinetic energy [J]
Ep = m*g*h
where:
m = mass of the rock = 45 [g] = 0.045 [kg]
g = gravity acceleration = 9.81 [m/s²]
h = elevation = (20 - 12) = 8 [m]
Ek = 0.5*m*v²
where:
v = velocity [m/s]
The reference level of potential energy is taken as the ground level, at this level the potential energy is zero, i.e. all potential energy has been transformed into kinetic energy. In such a way that when the Rock has fallen 12 [m] it is located 8 [m] from the ground level.
m*g*h = 0.5*m*v²
v² = (g*h)/0.5
v = √(9.81*8)/0.5
v = 12.52 [m/s]
Answer:
B AND D
HOPE ITS HELF FUL .........
Answer:
Note that both of the falsifiable claims in this example happen to be true. The claim about Kennedy being the 35th President is falsifiable because it can be checked against historical records. The claim that Kennedy died from a bullet in his brain is falsifiable because it could have been shown false by the medical examiner. The remaining claims are not falsifiable: Statements that call on any type of supernatural being are by definition out of the realm of science. Similarly, a claim of something being "undetectable" could not be falsified, and a claim about what Kennedy would have done if he had lived is a conjecture that cannot be disproven.
Explanation:
Answer:
So mass of the object will be 3.2 kg
Explanation:
We have net force on the object F = 16 N
Acceleration of the object 
We have top find the mass of the object
From newton law of motion we know that force is given by
F = ma , here m is mass and a is acceleration
So 

So mass of the object will be 3.2 kg