Answer:
B. Mechanical energy= 50J+30J=80J
Answer:
42.417 cm³
Explanation:
The formula to find the volume of a cone is :
V =
× π r² h
Here,
r ⇒ radius ⇒ 3 cm
h ⇒ height ⇒ 4.5 cm
<u>Let us find it now.</u>
V =
× π r² h
V =
× π × 3 × 3 × 4.5
V =
× π × 9 × 4.5
V =
× π × 9 × 4.5
V =
× π × 40.5
V =
× 3.142 × 40.5
V =
× 127.251
V = <u>42.417 cm³</u>
Complete Question
At what angle should the axes of two Polaroids be placed so as to reduce the intensity of the incident unpolarized light to 1/5.
Answer:
The angle is
Explanation:
From the question we are told that
The light emerging from second Polaroid is 1/5 the unpolarized
Generally the intensity of light emerging from the first Polaroid is mathematically represented as

Generally from the Malus law the intensity of light emerging from the second Polaroid is mathematically represented

=> 
=> 
From the question


=> ![\theta = cos ^{-1} [\sqrt{\frac{2}{5}} ]](https://tex.z-dn.net/?f=%5Ctheta%20%3D%20%20%20cos%20%5E%7B-1%7D%20%5B%5Csqrt%7B%5Cfrac%7B2%7D%7B5%7D%7D%20%20%5D)
=> 
The amplitude is 0.8 cm. The wavelength is 2.0 cm.