Answer:
Option B. 2.8 s
Explanation:
The following data were obtained from the question:
Initial velocity (u) = 27 m/s
Angle of projection (θ) = 30
Acceleration due to gravity (g) = 9.8 m/s²
Time of flight (T) =?
The time of flight of the ball can be obtained as follow:
T = 2uSineθ / g
T = 2 × 27 × Sine 30 / 9.8
T = 2 × 27 × 0.5 / 9.8
T = 27 / 9.8
T = 2.8 s
Therefore, time of flight of the ball is 2.8 s
Answer:
z = 0.8 (approx)
Explanation:
given,
Amplitude of 1 GHz incident wave in air = 20 V/m
Water has,
μr = 1
at 1 GHz, r = 80 and σ = 1 S/m.
depth of water when amplitude is down to 1 μV/m
Intrinsic impedance of air = 120 π Ω
Intrinsic impedance of water = 
Using equation to solve the problem

E(z) is the amplitude under water at z depth
E_o is the amplitude of wave on the surface of water
z is the depth under water



now ,


taking ln both side
21.07 x z = 16.81
z = 0.797
z = 0.8 (approx)
The planet is represented as Saturn ♄
Answer:
B) Diphosphorus pentoxide
Explanation: