The mass of a railway wagon is 1000 kN. If the coefficient of friction between the wheels and the railway track is 0.0002, then the force required for displacement of the wagon is

23) Estimate the time to drill a hole of 20 mm dia, 80 cm depth in mild steel. Take cutting speed of 15 meter /minute and feed of 0.25 mm/revolution.

24) In lead-acid battery, electrode lead peroxide and lead immersed in electrolyte of diluted solution of sulphur acid having _____ percentage of concentration for full charge.

25) Latent heat of ice is

26) A resistance having rating of 10 Ohm 10 W is likely to be a