Explanation:
Ohm's law states that the voltage or potential difference between two points is directly proportional to the current or electricity passing through the resistance, and directly proportional to the resistance of the circuit. The formula for Ohm's law is V=IR.
Frequency is given by the formula cycles÷seconds
So if the mosquito can complete 600 cycles in one second, our formula will be
f=600÷1
f=600!
The frequency is 600 Hz
Answer:

Explanation:
As we know that in AC circuit we have

here we have
V = 59 V
i = 5.05 A
so we will have


also we know that

here we will have


<h2>The increase in length = 1.87 x 10⁻²</h2>
Explanation:
When copper rod is heated , its length increases
The increase in length can be found by the relation
L = L₀ ( 1 + α ΔT )
here L is the increased length and L₀ is the original length
α is the coefficient of linear expansion and ΔT is the increase in temperature .
The increase in length = L - L₀ = L₀ x α ΔT
Substituting all these value
Increase in length = 27.5 x 1.7 x 10⁻⁵ x 35.9
= 1.87 x 10⁻² m
Answer: velocity of the car is 113.33m/s
Explanation:
From Doppler effect,
in the case which the source is moving towards the observer at rest
f2 = v/(v-vs) *f1
where f2 is the final observed frequency
f1 is the initial observed frequency
v = 340m/s (speed of sound in air)
vs = velocity of the source of sound.
rearranging the above equation
f2*(v - vs) = f1* v
vs = (f1* v/f2) - v
but f1 = 80Hz
f2 = 60Hz
v = 340m/s
substituting,
vs = (80 x 340)/60 - 340
vs = 453.33 - 340
vs = 113.33m/s
velocity of the car is 113.33m/s