(a) in tin at room temperature, the mobility of mobile electrons is about 1.5 ✕ 10-3 (m/s)/(v/m), and there are about 3.7 ✕ 1028 mobile electrons per m3. calculate the conductivity σ. in actual practice, it is usually easier to measure the conductivity σ and deduce the mobility u from this measurement.

diagram is missing, but i will try to explain your doubt.

answer:

amplitude is the maximum displacement or distance moved on a point of a vibrating body or wave measured from its equilibrium position.it is equal to half the length of vibration path.

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.

the tires are rotating at 0.434 rpmlinear speed=45 m/sdiameter=0.550 mradius=0.275 mnow v= rωω= v/rω=45/0.275ω=163.6 rad/sω=163.6 rad/s (1rev/2π rad) (60s/1m)ω=1563 rpm