A copper conductor of cross-sectional area 2.1 x 10^-6 m^2 carrying a current of
2.1 ampere. Find the mean velocity of electron flow in the conductor. The electron
concentration in copper is 8.5 x 10^28 m^3​

Awheel rotates without friction about a stationary horizontal axis at the center of the wheel. a constant tangential force equal to 82.0 n is applied to the rim of the wheel. the wheel has radius 0.150 m . starting from rest, the wheel has an angular speed of 12.8 rev/s after 3.88 s. what is the moment of inertia of the wheel?

Aplanet of mass m 6.75 x 1024 kg is orbiting in a circular path a star of mass m 2.75 x 1029 kg. the radius of the orbit is r 8.05 x107 km. what is the orbital period (in earth days) of the planet tplanet?

In automobile steering wheel is shown what is the ideal mechanical advantage blank? if the ama is eight what is the efficiency of the steering wheel?