Answer: c
Explanation:
Sound waves cannot travel through a medium
Physics contributes to the technological infrastructure and provides trained personnel need to take advantage of scientific advances and discoveries.
Physics is an important element in the education of chemists, engineers and computer scientists as well as practitioners of the other physical and biomedical sciences .
Assuming air as ideal gas and amount of air in no of moles is known then by gas law,
PV= nRT
Pressure is constant
P* (change in volume) = nR* (change in temperature)
Operation of a motor:
A motor takes electrical energy as input which energizes the windings of the motor and a changing magnetic field is generated which in turn generates force in the form of torque.
Let us have a look at the given options:
Option 1:
A motor works by changing the magnetic flux to change the voltage of a circuit.
This is incorrect.
Option 2:
A motor works by electrical energy moving a charge through a loop in a magnetic field, causing the loop to rotate.
This is the correct statement, this is how a motor operates.
Option 3:
A motor works by rotating a magnet in order to generate electricity.
This is incorrect since a motor consumes electricity (it does not generate electricity)
Option 4:
A motor works by using physical work to push a charge through a loop, generating a uniform magnetic field.
This is incorrect since a motor does not physical work to operate.
Therefore, the only correct statement is option 2
1. Frequency is the number of complete waves that pass a point in a second. 2.Wavelength is the distance between two crests or two troughs. 3.Time period <span> is the time it takes for one complete wave to pass a given point. 4. Amplitude is the height of the wave. Hence option 4 is correct. </span>