Answer: Longitudinal wave
Explanation:
Longitudinal wave are the oscillations that are parallel to the direction of energy transfer that means the vibrations are in line with the direction where the energy is travelling.
A key feature of sound wave is that they cause sound particles to vibrate. The region where the particles are close together are called compressions and regions where particles are further apart they are called rarefactions.
The other options explanation:
-Transverse waves are where the oscillations are perpendicular to the energy of transfer.
-A standing wave is where the waves are travelling back and forth where there are some fixed points in the system whilst other vibrate with highest amplitude
-Surface waves have both the characteristics of longitudinal and transverse waves
Answer:
The acceleration of the crate is 
Explanation:
Recall the formula that relates force,mass and acceleration from newton's second law;

Then in our case, we know the force applied and we know the mass of the crate, so we can solve for the acceleration as shown below:

Answer:
5miles North
Explanation:
The displacement to the store is 5miles northward.
Displacement is the distance traveled in a specific direction. Displacement is a vector quantity.
A vector has both magnitude and direction.
The magnitude is the amount of that quantity
The direction is its orientation from a reference.
Therefore, the displacement is 5miles north
Answer:
The refractive index of glass, 
Solution:
Brewster angle is the special case of incident angle that causes the reflected and refracted rays to be perpendicular to each other or that angle of incident which causes the complete polarization of the reflected ray.
To determine the refractive index of glass:
(1)
where
= refractive index of glass
= refractive index of glass
Now, using eqn (1)


