Answer:
The correct answer is b, x = 9 cos (pi / 2 t)
Explanation:
The equation that describes a simple pendulum is
θ = θ₀ cos (wt + φ)
The angle is measured is radians
θ = x / L
We replace
d / L = x₀ / L cos (wt + φ)
x₀ = 9 in
We replace
d = 9 cos (wt + φ)
Angular velocity is related to frequency and period.
w = 2π f = 2π / T
The period is the time of a complete oscillation T = 4 s
w =2π / 4
w = π / 2
Let's replace
x = 9 cos (π/2 t + φ)
As the system is released from the root x = x₀ for t = 0 s
x₀ = x₀ cos φ
Cos φ = 1
φ = 0°
The final equation is
x = 9 cos (pi / 2 t)
The correct answer is b
Answer:
unknown
Explanation:
Psi communication: The term "Psi communication" was initially originated in an article named 'Mass Communication and Para-Social Interaction' during 1956 by Donald Horton, and is also denoted as "parasocial interaction". It is described as a phenomenon that involves "one-sided interaction" between people, encompassing the viewer knowing a specific celebrity well whereas the viewer himself or herself is being completely unknown for the celebrity in return.
In the question above, the given statement represents that the Psi communication is responsible for transforming via an unknown process as one of its members are considered as unknown of the transfer, so the correct answer would be "unknown process".
Answer:
4.42 x 10⁷ W/m²
Explanation:
A = energy absorbed = 500 J
η = efficiency = 0.90
E = Total energy
Total energy is given as
E = A/η
E = 500/0.90
E = 555.55 J
t = time = 4.00 s
Power of the beam is given as
P = E /t
P = 555.55/4.00
P = 138.88 Watt
d = diameter of the circular spot = 2.00 mm = 2 x 10⁻³ m
Area of the circular spot is given as
A = (0.25) πd²
A = (0.25) (3.14) (2 x 10⁻³)²
A = 3.14 x 10⁻⁶ m²
Intensity of the beam is given as
I = P /A
I = 138.88 / (3.14 x 10⁻⁶)
I = 4.42 x 10⁷ W/m²
Answer:
about 2.7liters for women and 3.7liters for men
Explanation: