Answer:
The rate of change of the shadow length of a person is 2.692 ft/s
Solution:
As per the question:
Height of a person, H = 20 ft
Height of a person, h = 7 ft
Rate = 5 ft/s
Now,
From Fig.1:
b = person's distance from the lamp post
a = shadow length
Also, from the similarity of the triangles, we can write:

Differentiating the above eqn w.r.t t:
Now, we know that:
Rate = 
Thus
Answer:
Moment of inertia of the solid sphere:
I
s
=
2
5
M
R
2
.
.
.
.
.
.
.
.
.
.
.
(
1
)
Is=25MR2...........(1)
Here, the mass of the sphere is
M
M
Answer:
C because it is in earth's mantle
Answer:
6.71×10⁻⁷ m
Explanation:
Using thin film constructive interference formula as:
<u>2×n×t = m×λ</u>
Where,
n is the refractive index of the refracted surface
t is the thickness of the surface
λ is the wavelength
If m =1
Then,
2×n×t = λ
Given that refractive index pf the oil is 1.22
Thickness of the oil = 275 nm
Also, 1 nm = 10⁻⁹ m
Thickness = 275×10⁻⁹ m
So,
Wavelength is :
<u>λ= 2×n×t = 2× 1.22 × 275×10⁻⁹ m = 6.71×10⁻⁷ m</u>
Answer:
The centripetal acceleration
of an object moving in a uniform circular path is given by the following equation:

Where:
is the velocity
is the radius of the circle

