In a fly wheel,most of the mass is concentrated at the rim?Explain why?

A wheel of mass 1000 kg and radius 1 m is rotating at the rate of 420 r.p.m . What is the constant torque required to stop the wheel in 14 rotations , assuming the mass to be con-centrated at the rim of the wheel ?

Give reason for the following. a) atoms are electrically, neutral. b) Most of the mass of an atom is concentrated in its nucleus.

Blood pressure in humans is greater at the feet than at the brain. Explain why?

Bauxite, Al_2O_3.xH_2O is an important ore of aluminium. It is concentrated by leaching. Explain the method.

A cord of negligible mass in wound round the rim of flywheel of mass 20 kg and radius 20cm mounted on a horizontal axis Calculate the angular acceleration of the wheel if a steady pull of 25N is applied on the cord. Moment of inertia of flywheel about its axis= MR^2/2

Gallium has higher ionisation enthalpy than aluminium. Explain why?

Why is the fuse used in a circuit called safety fuse ? Explain.