1221. Which of the properties represent, cathode rays are negatively charged ?
A. Rotate small Paddle wheel
B. Deflected toward positively charged plate *
C. Deflected in magnetic field
D. Both B and C
1222. Cathode rays heat up when strike a thin metal foil because :
A. It has negative charge
B. It travel in straight line
C. It possess Kinetic Energy *
D. It has reducing effect
1223. Canal rays were discovered by:
A. Crooks
B. E.Goldstein *
C. R. Millikan
D. E. Rutherford
1224. Charge to mass ratio of canal rays depends upon :
A. Nature of gas *
B. Nature of Electrodes
C. Pressure
D. Voltage
1225. Which of the following gases when used in discharge tube will give lowest charge to mass ratio of canal rays ?
A. Hydrogen
B. Helium
C. Oxygen *
D. Nitrogen
1226. Unit of plank’s constant is :
A. J/sec
B. J.Sec *
C. J.m
D. J/m
1227. Ratio of radii of second and first orbit of hydrogen atom is :
A. 2
B. 3
C. 4 *
D. 5
1228. The radius of first orbit of hydrogen atom is 0.529 A degree. The radius of first orbit of LI2+ is:
A. 1.27 A degree
B. 0.17 A degree *
C. 0.57 A degree
D. 0.99 A degree
1229. ______ energy of electron is negative :
A. Kinetic
B. Potential
C. Total
D. Both B and C *
1230. Ratio of energy of photon of 250nm to that of 500nm is :
A. 1/2
B. 2 *
C. 1/4
D. 4