The Doppler Effect provides the equation for the
calculation of apparent frequency:
f=fo[vo/(vo-vr)]
where:<span>
vo=source wave velocity
vr=relative speed between source and observer
f=apparent frequency
fo=source frequency </span>
<span>
The velocity of the doppler wave is
v=λf</span>
where λ is light wavelength. Hence,
v=λfo[vo/(vo-vr)]
Based on the equation, we can say that wave
velocity will always be defined by one and only one wavelength.
Therefore the answer is letter C.
<span> </span>
It should be the B
Low frequency and long wavelength
Answer:
The car traveled the distance before stopping is 90 m.
Explanation:
Given that,
Mass of automobile = 2000 kg
speed = 30 m/s
Braking force = 10000 N
For, The acceleration is
Using newton's formula
Where, f = force
m= mass
a = acceleration
Put the value of F and m into the formula
Negative sing shows the braking force.
It shows the direction of force is opposite of the motion.
For the distance,
Using third equation of motion
Where, v= final velocity
u = initial velocity
a = acceleration
s = stopping distance of car
Put the value in the equation
Hence, The car traveled the distance before stopping is 90 m.
Explanation:
Let us first calculate long does it take to go 12m at 30m/s( assumed speed)
12/30 = 0.4 seconds
horizontal distance the ball drop in that time
H= (0)(0.4)+1/2(-9.8)(0.4)2
H= -0.78m
negative sign shows that the height of the ball at the net from the top.
Height of the ball at the net and from the ground= H1-H=2.4-0.78=1.62m
As 1.62m>0.9m so the ball will clear the net.
H_1= V0y t’ + ½ g t’^2
-2.4= (0)t’ + ½ (-9.8) t’^2
t’= 0.69s
X’=V0x t’
X’=(30)(0.96)
X’= 20.7m
Answer:
Explanation:
= Length of wire = 65 m
= Initial current = 1.8 A
= Final current = 2.9 A
We know
and
so
The length of the wire remaining on the spool is .
