Physics Past Questions and Answers

A metal of mass 0.5kg is heated to 100°C and then transferred to a well-lagged calorimeter of heat capacity 80JK^-1 containing water of heat capacity 420JK^-1 at 15°C. If the final steady temperature of the mixture is 25°C, find the specific heat capacity of the metal.

The main reason for making the cover of a vacuum flask airtight is to prevent heat loss by

A radio is operated by eight cells each of e.m.f. 2.0V connected in series. If two of the cells are wrongly connected, the net e.m.f. of the radio is

If a charged ion goes through combined electric and magnetic fields, the resultant emergent velocity of the ion is

A projection lantern is used to give the image of a slide on a screen. If the image is 24 times as large as the slide and the screen is 72.0m from the projecting lens, what is the position of the slide from the lens?