2nd and only 2nd option is right
Answer:
Explanation:
We shall apply the formula of Doppler effect here
F( APPARENT) = F( REAL ) X V/(V + Vs) [ v is velocity of sound and Vs is velocity of source.
415 = 440 X 343/343+Vs
142345 + 415Vs = 150920
415 V₀ = 8575
V₀ = 20.66 m/s.
Answer:
248
Explanation:
L = Inductance of the slinky = 130 μH = 130 x 10⁻⁶ H
= length of the slinky = 3 m
N = number of turns in the slinky
r = radius of slinky = 4 cm = 0.04 m
Area of slinky is given as
A = πr²
A = (3.14) (0.04)²
A = 0.005024 m²
Inductance is given as


N = 248
Answer B is the correct pair.
I'm Pretty sure it's FRICTION