6. Current in length of copper wire. Two students hold a 7.6 m length of copper wire horizontally, in an east-west direction, in the school yard. The wire is
moved vertically downwards at a speed of 0.30 ms?
Given that, in this yard, the horizontal component of the Earth's magnetic field is 4.0 x 10-5 T, and perpendicular to the
wire, calculate the emf detected, to two significant figures, by a very sensitive meter placed across the ends of the wire.

Astring that is fixed at both ends has a length of 1.05 m. when the string vibrates at a frequency of 91.0 hz, a standing wave with five loops is formed. (a) what is the wavelength of the waves that travel on the string? (b) what is the speed of the waves? (c) what is the fundamental frequency of the string?

Why is alchemy not considered to be a science ?

Asheet of steel 1.5 mm thick has nitrogen atmospheres on both sides at 1200oc and is permitted to achieve a steady-state diffusion condition. the diffusion coefficient for nitrogen in steel at this temperature is 6 x 10- 11 m2 /s, and the diffusion flux is found to be 1.2 x 10-7 kg/m2 -s. also, it is known that the concentration of nitrogen in the steel at the high-pressure surface is 4 kg/m3 . how far into the sheet from this high-pressure side will the concentration be 2.0 kg/m3 ? assume a linear concentration profile.