Answer:
The possible thickness of the soap bubble = 
Explanation:
<u>Given:</u>
- Refractive index of the soap bubble,

- Wavelength of the light taken,

Let the thickness of the soap bubble be
.
It is given that the soap bubble appears very bright, it means, there is a constructive interference takes place.
For the constructive interference of light through a thin film ( soap bubble), the condition of constructive interference is given as:

where
is the order of constructive interference.
Since the soap bubble is appearing very bright, the order should be 0, as
order interference has maximum intensity.
Thus,

It is the possible thickness of the soap bubble.
Like a grandfather clock,
A pendulum = a string with a weight(can be anything from a coin to a ring to a ball) is on the end, the pendulum swings back and forth losing a little bit of energy every swing until it comes to a complete stop
1 Ampere
Explanation:
1/R = 1/8 + 1/10 + 1/12
1/R = (30 + 24 + 20) / 240
1/R = 74 / 240
R = 240 / 37
R = 120/37 Ohms
We know that,
V = IR
I = V/R
I = 12 / (120/37)
I = 12 × 37/120
I = 37/10
I = 3.7 A
Now,
The current in 12 ohm resistor →
= 1 A
∴ The current in 12 ohm resistor is 1 ampere
Answer: option D) 42.4 N
The weight of the frame is balanced by the vertical component of tension.
W = T sin θ + T sin θ = 2 T sin θ
The tension in each cable is T = 30 N
Angle made by the cables with the horizontal, θ = 45°
⇒ W = 2×30 N × sin 45° = 2 × 30 N × 0.707 = 42.4 N
Hence, the weight of the frame is 42.4 N. Correct option is D.