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
The velocity of pin B after rod AB has rotated through 90* is vb = 3.2549 m/s.
<h3>What is Potential and Kinetic energy?</h3>
Potential energy is the energy that is stored in any item or system as a result of its location or component arrangement. The environment outside of the object or system, such as air or height, has no impact on it. In contrast, kinetic energy refers to the energy of moving particles inside a system or an item.
mass of rod, mab = 2.4kg
mass of rod, mbc = 4kg
conservation of energy
potential energy at position 1,
V1 = 2.5 * 9.81 * 0.18 + 4 * 9.81 * 0.18
V1 = 11.30112
kinetic energy T1 at position 1 is zero
potential energy at position 2 is zero
K.E at position 2,
= 1/3 *4 * (0.36)²
=0.10368kg m²
= 1/12 *4 * (0.6)²
=0.12kg m²
on putting the values in above equation we get,
T₂ = 1.0667vb²
0 + 11.30112 = 1.0667vb² + 0
vb = 3.2549 m/s
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Significant digits show the precision of measurements and calculations
Answer: i) 2.356 × 10^-3 m = 2.356mm, ii) 4.712 × 10^-3 m = 4.712mm
Explanation: The formulae that relates the position of a fringe from the center to the wavelength, distance between slits and distance between slits and screen is given below as
y = R×(mλ/d)
Where y = distance between nth fringes and the center fringe.
m = order of fringe
λ = wavelength of light = 589nm = 589×10^-9m
R = distance between slits and screen = 1.0m
d = distance between slits = 0.25mm = 0.00025m
For distance between the first dark fringe and the center fringe.
This implies that m = 1
y = 1 × 589×10^-9 × 1/0.00025
y = 589×10^-9/0.00025
y = 2,356,000 × 10^-9
y = 2.356 × 10^-3 m = 2.356mm
For the second dark fringe, this implies that m = 2
y = 1 × 2 × 589×10^-9/0.00025
y = 1178 × 10^-9 /0.00025
y = 4,712,000 × 10^-9
y = 4.712 × 10^-3 m = 4.712mm
