Answer:
λ = 5940 Angstroms
Explanation:
This is an exercise of the relativistic Doppler effect
f’= f √((1- v / c) / (1 + v / c))
Where the speed in between the strr and the observer is positive if they move away
Let's use the relationship
c = λ f
f = c /λ
We replace
c /λ’ = c /λ √ ((1- v / c) / (1 + v / c))
λ = λ’ √ ((1- v / c) / (1 + v / c))
Let's calculate
v = 0.01 c
v = 0.01 3 10⁸
v= 3 10⁶ m / s
λ = 6000 √ [(1- 3 10⁶/3 10⁸) / (1+ 3 10⁶/3 10⁸)]
λ = 6000 √ [0.99 / 1.01]
λ = 5940 Angstroms
<em>1</em><em>.</em><em>259ms^2</em>
Explanation:
since, WORK DONE = FORCE*DISTANCE
AND, FORCE=MASS*ACCELERATION
SO, THE WORK DONE BECOMES=MASS*ACCELERATION*DISTANCE
ACCELERATION=WORK/(MASS*DISTANCE)
AND, WORK=686J
MASS=227kg
DISTANCE=2.4m
THEREFORE, ACCELERATION=686/(227*2.4)
=686/544.8
=1.259ms^2
A., 101.7 km/h is the correct answer for this question
I think you almost got it.
At the top, the velocity only has horizontal component, so v=12 m/s is v_x, which is v*cos(theta), because v_x is constant, so the same when it was launched or now.
With the value of the initial speed (28 m/s, which is the total speed), you can set
v_x = v * cos( theta ) ---> 12 = 28*cos(theta) --> cos(theta)=12/28=3/7
or theta = 64.62 deg, it is D. Think about it. I hope you see it.