A child applies a 4 N force for 1 m in the same direction a toy car is already moving, what is the change in the kinetic energy of the car? a 40 J
b 4 J
c 1 J
d Unable to determine

In a vernier instrument the main scale is in 1/2 mm divisions .vernier is made by redividing 19 such divisions into 20 equal parts. calculate the least count of the instrument.

Air is to be preheated by hot exhaust gases in a cross-flow heat exchanger before it enters the furnace. air enters the heat exchanger at 95 kpa and 20°c at a rate of 0.6 m^3/s. the combustion gases (cp = 1.10 kj/kg°c) enter at 160°c at a rate of 0.95 kg/s and leave at 95°c. determine the rate of heat transfer to the air and its outlet temperature.

Which of the following is not a physical property of mattera. melting pointb.heat of combustionc. viscosityd. boiling point