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)
Your answer is A. Vibrate in place
Answer:
Friction acts in the opposite direction to the motion of the truck and box.
Explanation:
Let's first review the problem.
A moving truck applies the brakes, and a box on it does not slip.
Now when the truck is applying brakes, only it itself is being slowed down. Since the box is slowing down with the truck, we can conclude that it is friction that slows it down.
The box in the question tries to maintains its velocity forward when the brakes are applied. We can think of this as the box exerting a positive force relative to the truck when the brakes are applied. When we imagine this, we can also figure out where the static friction will act to stop this positive force. Friction will act in the negative direction. Or in other words, friction will act in the opposite direction to the motion of the truck and box. This explains why the box slows down with the truck, as friction acts to stop its motion.
is the best estimate of the density of the air on the planet.
Given:
The mass of the conical flask with stopper is 457.23 grams and the volume is .
Mass of conical flask and a stopper after removing the air is 456.43 g
To find:
The density of the air on the planet.
Solution;
Mass of the conical flask and stopper with air on the planet= 457.23 g
Mass of conical flask with a stopper and without air on the planet = 456.43 g
Mass of the air in the conical flask on the planet =m
The volume of the conical flask =
The volume of the air in the conical flask =
The density of the air on the planet = d
is the best estimate of the density of the air on the planet.
Learn more about density here:
brainly.com/question/952755?referrer=searchResults
brainly.com/question/14373997?referrer=searchResults
Answer:
<h3>Using Newtons Second law of motion</h3>
Explanation:
Newtons Second law of motion states that the rate of change momentum of a system is directly proportional to unbalanced External force acting on it.
if we consider all colliding particles as a system we can see there is no external forces acting on the system. the forces that present here due to collision are internal forces
so As per newtons second law moment should be conserved for the colliding particles.