Question

29. x is directly proportional to 4 more than the square of
yox is 39 when y is 3. What is the positive value of y
when x is 60? answer explain ​

Answer 1

Answer:

Answer:-

Time period is 2.16 × 10⁻¹⁵ [Option.B]

Explanation:-

We have :-

→ Wavelength of red light = 6500 Å

= 6.5 × 10⁻⁷ m

→ Velocity of light = 3 × 10⁸ m/s

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Firstly let's calculate the frequency of the red light. We know that :-

ν = c/λ

⇒ ν = [3×10⁸]/[6.5×10⁻⁷]

⇒ ν = 0.46 × 10¹⁵

⇒ ν = 4.6 × 10¹⁴ Hz

Now :-

T = 1/ν

⇒ T = 1/[4.6 × 10¹⁴]

⇒ T = 0.216 × 10⁻¹⁴

⇒ T = 2.16 × 10⁻¹⁵ second

Answer 2

Answer:

4

Step-by-step explanation:

Given,

x ∝ 4+y²

x=k(4+y²)

if x=39 then y =3 so we get the value of k

39=k(4+9)

k=3

Now, we have to find the y if x=60

so

x=k(4+y²)

60=3(4+y²)

20=4+y²

y=4