Answer:
V = 49.05 [m/s]
Explanation:
We can easily find the result using kinematics equations, first, we will find the distance traveled during the 5 seconds.
where:
Yo = initial position = 0
y = final position [m]
Vo = initial velocity = 0
t = time = 5 [s]
g = gravity aceleration = 9.81 [m/s^2]
The initial speed is zero, as the body drops without imparting an initial speed. Therefore:
y = 0 + (0*5) + (0.5*9.81*5^2)
y = 122.625[m]
Now using the following equation we can find the speed it reaches during the 5 seconds.
Answer:
The final velocity of the wooden block is equal to
Explanation:
Given that mass of bullet =
Mass of wood =
Initial velocity of bullet =
Final velocity of bullet =
Initial velocity of wood = o
Final velocity of wood =
Here momentum is conserved so initial momentum = final momentum
.
Upon substituting these values in above equation , we get
.
Answer:
the required minimum length of the attenuator is 3.71 cm
Explanation:
Given the data in the question;
we know that;
= c / 2a
where f is frequency, c is the speed of light in air and a is the plate separation distance.
we know that speed of light c = 3 × 10⁸ m/s = 3 × 10¹⁰ cm/s
plate separation distance a = 7.11 mm = 0.0711 cm
so we substitute
= 3 × 10¹⁰ / 2( 0.0711 )
= 3 × 10¹⁰ cm/s / 0.1422 cm
= 21.1 GHz which is larger than 15 GHz { TEM mode is only propagated along the wavelength }
Now, we determine the minimum wavelength required
Each non propagating mode is attenuated by at least 100 dB at 15 GHz
so
Attenuation constant TE₁ and TM₁ expression is;
∝₁ = 2πf/c × √( ( / f)² - 1 )
so we substitute
∝₁ = ((2π × 15)/3 × 10⁸ m/s) × √( (21.1 / 15)² - 1 )
∝₁ = 3.1079 × 10⁻⁷
∝₁ = 310.79 np/m
Now, To find the minimum wavelength, lets consider the design constraint;
20log₁₀ = -100dB
we substitute
20log₁₀ = -100dB
= 3.71 cm
Therefore, the required minimum length of the attenuator is 3.71 cm