Answer:
s = 27 m
Explanation:
given,
acceleration of the car, a = 6 m/s²
time of the travel, t = 3 s
final speed of the car, v = 0 m/s
using equation of motion
v = u + a t
0 = u - 6 x 3
u = 18 m/s
initial speed of the car = 18 m/s
Again using equation of motion
v² = u² + 2 a s
0 = 18² - 2 x 6 x s
12 s = 324
s = 27 m
Distance travel by the car is equal to 27 m.
Answer:
80mm or 8cm
Explanation:
According to the lens formula,
1/f = 1/u+1/v
If the object distance u = 4cm = 40mm
Object height = 1.5mm
Image height = 3mm
First, we need to get the image distance (v) using the magnification formula Magnification = image distance/object distance = Image height/object height
v/40=3/1.5
1.5v = 120
v = 120/1.5
v = 80mm
The image distance is 80mm
To get the focal length, we will substitute the image distance and the object distance in the mirror formula to have;
1/f = 1/40+1/-80
Note that the image formed by the lens is an upright image (virtual), therefore the image distance will be negative.
Also the focal length of the converging lens is positive. Our formula will become;
1/f = 1/40-1/80
1/f = 2-1/80
1/f = 1/80
f = 80mm
The focal length of the lens 80mm or 8cm
The sound waves travel because of the pitch of the note so the window rattles.
Answer:
the inductive reactance of the coil is 1335.35 Ω
Explanation:
Given;
inductance of the coil, L = 250 mH = 0.25 H
effective current through the coil, I = 5 mA
frequency of the coil, f = 850 Hz
The inductive reactance of the coil is calculated as;
Therefore, the inductive reactance of the coil is 1335.35 Ω