IIT-JEE Exam

When two identical batteries of internal resistance 1Ω each are connected in series across a resistor R, the
rate of heat produced in R is J1. When the same batteries are connected in parallel across R, the rate is J2. If
J1 = 2.25 J2 then the value of R in Ω is

Read Solution (Total 0)

IIT-JEE Other Question

A stationary source is emitting sound at a fixed frequency f0, which is reflected by two cars approaching the
source. The difference between the frequencies of sound reflected from the cars is 1.2% of f0. What is the
difference in the speeds of the cars (in km per hour) to the nearest integer ? The cars are moving at constant
speeds much smaller than the speed of sound which is 330 ms–1. A piece of ice (heat capacity = 2100 J kg–1 º C–1 and latent heat = 3.36 × 105 J kg–1) of mass m grams is at –
5ºC at atmospheric pressure. It is given 420 J of heat so that the ice starts melting. Finally when the ice–
water mixture is in equilibrium, it is found that 1 gm of ice has melted. Assuming there is no other heat
exchange in the process, the value of m is