Answer:
39.2m/s
Explanation:
Given parameters:
Mass of book = 5kg
Time taken for fall = 4s
Unknown:
Final velocity of the book = ?
Solution:
Serena dropped the book from rest therefore, the initial velocity of the book is 0.
Let us find the appropriate motion equation to solve this problem;
V = U + gt
V is the final velocity
U is the initial velocity
g is the acceleration due to gravity = 9.8m/s²
t is the time taken
Insert the given parameters and solve;
V = 0 + 9.8 x 4 = 39.2m/s
Answer:
average speed = total distance/total time
Answer:
Explanation:
The case relates to interference in thin films , in which we study interference of light waves reflected by upper and lower surface of a medium or glass.
For constructive interference , the condition is
2μt = ( 2n+1)λ/2
μ is refractive index of glass , t is thickness , λ is wavelength of light.
putting the given values
2 x 1.53 x 350 x 10⁻⁹ = ( 2n+1) λ/2
λ = 2142nm / ( 2n+1)
For n = 2
λ = 428 nm
This wave length will have constructive interference making this light brightest of all .
For n = 1
λ = 714 nm
So second largest brightness will belong to 700 nm wavelength.
Answer:
Explanation:
Given that,
Charge through a wire is
Q = 4000C
Time for charge to pass through the wire is
t = 50seconds
Then,
Current through the wire is the rate of charge passing through the wire
Q = it
Where
Q is charge.
I is current
t is time taken
Therefore,
I = Q / t
I = 4000 / 50
I = 80 Amps
