Velocity is a vector quantity i.e. it has both magnitude and direction
Speed is a scalar quantity i.e. it has only magnitude
(a) The stone travels a vertical distance <em>y</em> of
<em>y</em> = (12.0 m/s) <em>t</em> + 1/2 <em>g t</em> ²
where <em>g</em> = 9.80 m/s² is the acceleration due to gravity. Note that this equation assume the downward direction to be positive, and that <em>y</em> = 0 corresponds to the height from which the stone is thrown.
So if it reaches the ground in <em>t</em> = 1.54 s, then the height of the building <em>y</em> is
<em>y</em> = (12.0 m/s) (1.54 s) + 1/2 (9.80 m/s²) (1.54 s)² ≈ 30.1 m
(b) The stone's (downward) velocity <em>v</em> at time <em>t </em>is
<em>v</em> = 12.0 m/s + <em>g t</em>
so that after <em>t</em> = 1.54 s, its velocity is
<em>v</em> = 12.0 m/s + (9.80 m/s²) (1.54 s) ≈ 27.1 m/s
(and of course, speed is the magnitude of velocity)
Answer: 50J
Explanation:
Mechanical energy follows the same principles of kinetic energy and potential energy, it is conserved. So Ei = Ef.
Mechanical energy is the sum of ALL energy's. There is no friction, so its just kinetic plus potential.
37.5 + 12.5 = 50J
Since the particle has not touched the ground, it has not transferred any energy to the ground yet, therefore the mechanical energy must still be 50J; mostly in kinetic energy with a very small amount of potential because of the low height relative to the ground.
A. Because they reflect their color and absorb all the others
To solve this problem we will apply the concepts of equilibrium and Newton's second law.
According to the description given, it is under constant ascending acceleration, and the balance of the forces corresponding to the tension of the rope and the weight of the elevator must be equal to said acceleration. So
Here,
T = Tension
m = Mass
g = Gravitational Acceleration
a = Acceleration (upward)
Rearranging to find T,
Therefore the tension force in the cable is 10290.15N
