Question

1.A room of 1.5 litres contains gas with pressure 10^5 Pa.If the gas particle has average speed of 750 m/s,then gas mass that trapped in the room is...gram

A.0.8
B.0.7
C.0.6
D.0.5
E.0.4


2.An object is placed 375 mm in front of a concave mirror with focus 250 mm.If the object is moved 25 mm away from the mirror,then it's shadow will shift to...mm

A.80
B.82
C.83
D.84
E.85


3.If purple light frequency of 10^16 Hz falls on a metal surface with verge energy 1/3 of energy quanta of the purple light.The kinetic energy of the released electron is...X 10^-18J

A.6.6
B.4.4
C.3.3
D.2.2
E.1.1