Differences b/w an motor n an electromagnet r :
1- motor is a device which converts electrical energy into mechanical energy while an electromagnet is just a combination of a soft iron core + solenoid....
2- electromagnets r strong temporary magnets while motors don't behave like a magnet
It depends on A) how fast the wire vibrates because sound is produced by vibration
Answer:electrostatic interactions, hydrogen bonding, van der waals interactions.
Explanation:the above listed are the interaction that that contribute
Answer:
A=
Explanation:
We have given power =40 W but only 10% of this power is used so actual power 
We know that from Stefan's law 
where 
is Boltzmann constant which value is 
So 
A=
Answer:
Explanation:
Total internal reflection can happen when light goes from a medium with higher refractive index (in this case, glass) to a medium with lower refractive index (in this case, water).
Snell's Law tells us that 
, where the <em>i</em> stands for incident (in this case, glass) and the <em>r</em> for refracted (in this case, water). We want to know when 
, that is, when 
, and this happens when the incident angle is:
Which for our values means:
