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Answer: D) 30</h3>
Angle of incidence always equals angle of reflection. Think of a tennis ball being hit into a wall. The ball will bounce off at the same angle that it approached with. The angles mentioned are formed through the line called the "normal", which is the line perpendicular to the surface.
Answer:
9000RPM
Explanation:
"Angular velocity" is directly related to kinetic energy, that is, the Kinetic energy equation would allow an approximation to the resolution investigated in the problem.
The equation for KE is given by:
Now, starting from there towards the <em>Angular equation of kinetic energy</em>, the moment of inertia (i) is used instead of mass (m), and angular velocity (w) instead of linear velocity (V)
That's how we get
calculating the inertia for a solid cylindrical disk, of
m = 400kg
r = 1.2 / 2 = 0.6m
We understand that the total kinetic energy is 3.2 * 10 ^ 7J, like this:
Thus,
943 rad / s ≈ 9000 rpm
Ye sit does. But since people weren’t there to hear it, doesn’t mean that it didn’t make a sound.
Answer:
a) Acceleration is zero
, c) Speed is cero
Explanation:
a) the equation that governs the simple harmonic motion is
x = A cos (wt +φφ)
Where A is the amplitude of the movement, w is the angular velocity and φ the initial phase determined by the initial condition
Body acceleration is
a = d²x / dt²
Let's look for the derivatives
dx / dt = - A w sin (wt + φ)
a = d²x / dt² = - A w² cos (wt + φ)
In the instant when it is not stretched x = 0
As the spring is released at maximum elongation, φ = 0
0 = A cos wt
Cos wt = 0 wt = π / 2
Acceleration is valid for this angle
a = -A w² cos π/2 = 0
Acceleration is zero
b)
c) When the spring is compressed x = A
Speed is
v = dx / dt
v = - A w sin wt
We look for time
A = A cos wt
cos wt = 1 wt = 0, π
For this time the speedy vouchers
v = -A w sin 0 = 0
Speed is cero
