Answer:
option C
Explanation:
The correct answer is option C
A light that transmits through n₂ travels t distance before reflection off the n₁ medium and again travels distance t before reaching the point from where it entered n₂ medium. Hence it travels 2 t distance more than the light that is reflected off n₂.
It( light entering n₂) also travels an additional distance equal to, half of the wavelength, when reflected off n₁ ( as n₁ is greater than n₂).
Wavelength in n₂ is = 
Hence, path length difference = 
If a constant force is applied on a body, the body moves with constant acceleration.
Answer:
P = 97.2 W
Explanation:
Given that,
Voltage drop, V = 54 V
The resistance of the resistor, R = 20 Ohms
Current, I = 1.8 A
We need to find the power used by the resistor. The formula used to find the power is given by :
P = VI
Putting all the values,
P = 54 V × 1.8 A
P = 97.2 W
So, the power used by the resistor is 97.2 W.
Displacement is d
Vf² = Vi² + 2 g d
(-20²) = (+10²) + 2 (-9.8) d
-19.6 d = 300
d = -15.3 m
negative means lower
time is t
d = Vi t + 1/2 g t²
-15.3 = 10 t + (-4.9) t²
4.9 t² - 10 t -15.3 = 0
t = 3.06 s
Answer is 6.84 approx
reason:-
(2.78^2+6.25^2)^1/2=6.84 approx
