Humans hear frequencies from 20 Hz<span> (low) up to </span>20,000 Hz (high)
Multiplying the power of any signal by 5 can be described as
an increase of 6.99 dB .
If the whistle blew at 70 dB initially, and its sound power became
multiplied by 5, and the whistle and the listener both stayed in
the same places, then the listener would tell you that the whistle
was now blowing at 76.99 dB .
(More likely, he would report "77 dB" as he held his ears and winced.)
Answer
Assuming
east is the positive x direction
north is the positive y direction
initial velocity , u = 19 j m/s
a)
acceleration , a = 1.6 j m/s^2
Using first equation of motion
v = u + a × t
v = 19 + 5.6× 1.6
v = 28 j m/s
the velocity of the car after 5.6 s is 28 m/s north
b)
acceleration , a = -1.5 j m/s^2
Using first equation of motion
v = u + a × t
v = 19 - 5.6 ×1.5
v = 10.6 j m/s
the velocity of the car after 5.6 s is 10.6 m/s north
Their combined momentum after they meet is 0 .
Answer:
1. Lateral inversion is a phenomenon in which left appears to be right and vice versa. It is due to direction that light follows when it strikes a reflecting surface, generally a mirror.
These are the letters which don't show lateral inversion A,H,O,T,U
2. USES OF CONCAVE MIRROR
They are used as shaving mirrors to see a larger image of the face.
Dentists use concave mirrors to view large images of the teeth of the patients.
USES OF CONVEX MIRROR
It is is used as a rear view mirror in vehicles.
It is used as a vigilance mirror.
