<span>Pressure = force / area</span>
I assume that 350kg is the mass
Therefore,
350 x 9.8 (gravity) = 3430N
3430 / 1 = 3430Pa
3.43 KPa
Solution :
The given figure is a loop of a wire with a resistor.
When the switch S is closed for long time and is suddenly opened, the direction of the induced current can be find out by using the rule of right hand screw. According to the right hand screw rule, the direction of the magnetic field at the loop is in the direction that points outwards. The strength of the current rapidly decreases as it is switch off and the magnetic flux that is linked with the loop wire will also decrease.
According to the Lenz's law, the direction of the induced current must be such 
the decrease in the magnetic flux. It means the direction of the magnetic field must be outwards and also normal to the plane of the screen. The direction of the induced anti clockwise or from right to left in the resistance.
The part you talk into, that converts the sound of your voice
into an electrical signal, is a tiny microphone.
-- The sound waves from your voice are ripples in the air.
-- In most microphones, there's a tiny coil of wire hanging
between the ends of a tiny magnet.
-- When the ripples in the air hit the little coil of wire, they
make it vibrate (wiggle) slightly.
-- When a coil of wire wiggles in the field of a magnet,
a current flows in the wire.
There's your electrical signal !
It could rotate while not advancing distance
