C. electrical energy is transformed into light and heat energy
on touching electroscope gets positively charged, so answer is B. conduction
Answer:
=99.07nm
Explanation:
minimum thickness
2nd = (m - 1/2)λ
d = (m - 1/2)(λ/2n)
refractive index of the thin film, n = 1.34
minimum thickness m = 1
light wavelength λ = 531nm
d = (1 - 1/2) (531 / (2)(1.34)
d = 531/5.36
= 99.07nm
Answer:
Explanation:
A )
At the bottom of the circle , the potential energy of the stopper is converted into kinetic energy
1/2 m V² = mg x 2r + 1/2 mv²
m is mass of stopper , V is velocity at the bottom , r is radius of the circular path which is length of the string , v is velocity at the top
1/2 V² = g x 2r + 1/2 v²
V² = g x 4r + v²
V² = 9.8 x 4 + 8²
V² = 103.2
V = 10.16 m/s
B )
If T be the tension at the top
Net downward force
= mg + T . This force provides centripetal force for the circular motion
mg +T = mv² / r
T = mv²/r -mg
= m ( v²/r - g )
= .005 ( 8²/1 -g )
= .005 x 54.2
= .27 N .
C ) At the bottom
Net force = T - mg , T is tension at the bottom , V is velocity at bottom
T-mg = mV²/r
T = m ( V²/r +g )
= .005 ( 10.16²/1 +9.8)
= .005 x 113
= .56 N .
