Answer:
a. Wavelength = λ = 20 cm
b. Next distance of maximum intensity will be 40 cm
Explanation:
a. The distance between the two speakers is 20cm. SInce the intensity is maximum which refers that we have constructive interference and the phase difference must be an even multiple of π and equivalent path difference is nλ.
Now when distance increases upto 30 cm between the speakers, the sound intensity becomes zero which means that there is destructive interference and equivalent path is now increased from nλ to nλ + λ/2.
This we get the equation:
(nλ + λ/2) - nλ = 30-20
λ/2 = 10
λ = 20 cm
b. at what distance, sound intensity will be maximum again.
For next point calculation for maximum sound intensity, the path difference must be increased (n+1) λ. The distance must increase by λ/2 from the point of zero intensity.
= 30 + λ/2
= 30 + 20/2
=30+10
=40 cm
The factor that most affects the flow of ocean currents is B. differences in temperaturethreAnswer here
As the temperature of water increases, the density of water will decrease.
Answer:
If the frequency of the source is increased the current in the circuit will decrease.
Explanation:
The current through the circuit is given as;

Where;
V is the voltage in the AC circuit
Z is the impedance

Where;
R is the resistance
is the inductive reactance
= ωL = 2πfL
where;
L is the inductance
f is the frequency of the source
Finally, the current in the circuit is given as;

From the equation above, an increase in frequency (f) will cause a decrease in current (I).
Therefore, If the frequency of the source is increased the current in the circuit will decrease.
Answer: - 25.2 kgm/s
Explanation: The mass of the ball is 0.5kg, and the initial velocity = 10.6m/s.
The final velocity is in opposite direction of the initial hence final velocity (v) = - 19.9 m/s
Impulse = change in momentum = final momentum - initial momentum.
Final momentum = mass × final velocity
Final momentum = - 19.9 × 0.5
Final momentum = - 9.95 kgm/s
Initial momentum = mass × initial velocity
Initial momentum = 0.5 × 10.6 = 5.3kgm/s
Change in momentum = final momentum - initial momentum = - 19.9 - 5.3
Change in momentum = - 25.2 kgm/s
The negative sign implies that the change in momentum is the opposite direction relative to the first.