Near the surface of reflection, reflected wave may interfere with incident wave leading to production of constructive and as well as destructive interference. This in turn, can result to resonance as well as enhancement of the sound intensity as the waves of reflection adds to incident wave. Therefore, the girl would higher intensity of reflected waves as compared to incident waves.
Therefore, statement A is correct.
Answer:
On the magnitude of the charges, on their separation and on the sign of the charges
Explanation:
The magnitude of the electric force between two charges is given by

where
k is the Coulomb's constant
q1, q2 are the magnitudes of the two charges
r is the separation between the charges
From the formula, we see that the magnitude of the force depends on the following factors:
- magnitude of the two charges
- separation between the charges
Moreover, the direction of the force depends on the sign of the two charges. In fact:
- if the two charges have same sign, the force is repulsive
- if the two charges have opposite signs, the force is attractive
Answer: They will repel each other.
Explanation:
Two inflated balloons when rubbed with woolen cloth will lead to repeal each other because of the similar charges on both the balloons.
Rubbing both the balloons together by the woolen cloth will introduce negative charge in the balloons.
As, we know that the same charges repeal each other both of the balloons with be apart from each other.
This is due to the static electricity, the negatively charged particles jump to the positive one. When balloons are rubbed they become negatively charged.
Explanation:
When the wire is connected to a battery, the compass needle moves and changes its position. This happens because the needle magnetizes the copper wire, thus, creating a force.
While the current in the wire produces a magnetic field and exerts a force on the needle. The insulation on the wire becomes energized and exerts a force on the needle. Hence, the compass needle moves and changes its position.
Answer:
θ = 41.80°
Explanation:
Given that
Mach number M= 1.5
We know that
M = u/c
Where c is the velocity of sound and u is the speed of plane
c= 340 m/s
So
u = 1.5 x 340 m/s
u = 510 m/s
We know that

Now by putting the values


θ = 41.80°
So the angle will be 41.80°.