Answer:
The length of the stick is 0.28 m.
The time the stick take to move is 0.97 ns.
Explanation:
Given that,
Relative speed of stick v= 0.96 c
Speed of light 
Proper length of stick = 1 m
We need to calculate the length of the stick
Using formula of length

Put the value into the formula



We need to calculate the time the stick take to move
Using formula of time

Put the value into the formula



Hence, The length of the stick is 0.28 m.
The time the stick take to move is 0.97 ns.
Answer:
Efficiency = 52%
Explanation:
Given:
First stage
heat absorbed, Q₁ at temperature T₁ = 500 K
Heat released, Q₂ at temperature T₂ = 430 K
and the work done is W₁
Second stage
Heat released, Q₂ at temperature T₂ = 430 K
Heat released, Q₃ at temperature T₃ = 240 K
and the work done is W₂
Total work done, W = W₁ + W₂
Now,
The efficiency is given as:

or
Work done = change in heat
thus,
W₁ = Q₁ - Q₂
W₂ = Q₂ - Q₃
Thus,

or

or

also,

or

thus,

thus,

or

or
Efficiency = 52%
The crest of the wave has traveled 415 cm in 11.7s. then the crest should have travelled 415/11.7 cm in one second i.e. 35.47cm. Then the crest should have travelled 26*35.47 cm in 26 seconds i.e. 922.2cm which has 46 vibrations in it.
so for length of each vibration (Wavelength) is 20 cm
-- Equations #2 and #6 are both the same equation,
and are both correct.
-- If you divide each side by 'wavelength', you get Equation #4,
which is also correct.
-- If you divide each side by 'frequency', you get Equation #3,
which is also correct.
With some work, you can rearrange this one and use it to calculate
frequency.
Summary:
-- Equations #2, #3, #4, and #6 are all correct statements,
and can be used to find frequency.
-- Equations #1 and #5 are incorrect statements.
Electrical energy is and 100% correct answer