Answer:

Explanation:
By applying the Law of Sines,

Based on Newton's Law,

And the final equation also derived from Newton's Law,

Then by consolidating all the equations together,


Thus,

The correct term is accretion disk. This refers to a formation, typically a circumstellar disk, created by dispersed matter revolving around a large central body, which is usually a star. The gravitational pull causes the material in the disk to spiral inward towards the center.
Answer:
The beats frequency measures approximately
4.4 kHz
Explanation:
The beat frequency arises from the original ultrasound frequency,
, and the frequency of the sound reflected off the car,
:
(1)
To calculate the frequency of the reflected sound, we apply the Doppler effect formula:

where
v = 340 m/s, the speed of sound
is the velocity of the car
is the frequency of the sound emitted
By substituting values,

Thus, the beat frequency (1) is

Answer:
W = 294 J
Explanation:
provided,
mass of the projectile = 2 Kg
horizontal displacement = 20 m
vertical displacement = 15 m
work performed by the gravitational force =?
the work done by gravitational force only accounts for vertical motion.
force due to gravity = m g
= 2 x 9.8 = 19.6 N
work is equal to force x displacement
W = F x s
W = 19.6 x 15
W = 294 J