Answer:
f = 4000 / 30 sec = 133.3 vibrations/sec
P = 1 / f = .0075 sec period of 1 vibration
The correct answer is letter b.
To find the answer follow the following steps.
1. 6524.96 x .25 = X
2. 1631.24 = X
This works for all of the given answers to find the correct answer.
Explanation:
It is given that,
A planet were discovered between the sun and Mercury, with a circular orbit of radius equal to 2/3 of the average orbit radius of Mercury.
Mass of the Sun, 
Radius of Mercury's orbit, 
Radius of discovered planet, 

Let T is the orbital period of such a planet. Using Kepler's third law of planetary motion as :




T = 4135214.625 s
or
T = 47.86 days
So, the orbital period of such a planet is 47.86 days. Hence, this is the required solution.
Answer:
Explanation:
The angle of incidence and refraction are both measured from the normal
angle of incidence = 30°
angle of refraction = 23°
refractive index(n) = sini / sinr
n = sin30°/sin23°
n = 1.27965
refractive index (n) = 1/sinC
where C is the critical angle.
sinC= 1/n
C =arcsin (1/n)
C =arcsin (1/1.27965)
C = 51.39°
Answer:
6.39×10^23 kg is the weight on mass