Answer:
Bottle opener works on a fulcrum.
Explanation:
A bottle opener is a second-class lever because the pivot point is at one end of the opener and the load is in the middle.
Answer:
(C) The frequency decrease and intensity decrease
Explanation:
The Doppler effect describes the change in frequency or wavelength of a wave in relation to an observer who is moving relative to the wave source, or the wave source is moving relative to the observer, or both.
if the observer and the source move away from each other as is the case for this problem, the wavelength heard by the observer is bigger.
The frequency is the inverse from the wavelength, so the frequency heard will increase.
The sound intensity depends inversely on the area in which the sound propagates. When the buzzer is close, the area is from a small sphere, but as the buzzer moves further away, the wave area will be from a larger sphere and therefore the intensity will decrease.
Answer:
Speed = 300 m/s
Explanation:
Given the following data;
Frequency = 150 Hz
Wavelength = 2 meters
To find the speed of the wave;
Mathematically, the speed of a wave is given by the formula:
Substituting into the formula, we have;
Speed = 300 m/s
Answer:
6.03 mV
Explanation:
length of solenoid, L = 2 m, N = 12000, di/dt = 40 A/s,
Magnetic field due to solenoid
B = μ0 n i = μ0 N i / L
dB/dt = μ0 N / L x di / dt
dB /dt = (4 x 3.14 x 10^-7 x 12000 x 40) / 2 = 0.3 T/s
Induced emf, e = rate of change of magnetic flux
e = dΦ / dt = A x dB / dt
e = 3.14 x 0.08 x 0.08 x 0.3 = 6.03 x 10^-3 V = 6.03 mV
