Jamb 2000 Physics Past Questions And Answers
If the fraction of the atoms of a radioactive material left after 120years is 1/64, what is the half-life of the material?
- A. 24 years
- B. 20 years
- C. 10 years
- D. 2 years
A travelling wave moving from left to right has an amplitude of 0.15m, a frequency of 550Hz and a wavelength of 0.01m. The equation describing the wave is
- A. y = 0.15 sin 200π(x - 5.5t)
- B. y = 0.15 sin π(0.01x - 5.5t)
- C. y = 0.15 sin 5.5π(x - 200t)
- D. y = 0.15 sin π(550x - 0.01t)
A certain radioactive source emits radiations that were found to be deflected by both magnetic and electric fields. The radiations are
- A. beta rays
- B. gamma rays
- C. x-rays
- D. ultrar-violet rays
The velocity y of a particle in a time t is given by the equation y = 10 + 2t2
Find the instantaneous acceleration after 5 seconds
- A. 60 ms-2
- B. 20 ms-2
- C. 15 ms-2
- D. 10 ms-2
A catapult used to hold a stone of mass 500g is extended by 20cm with an applied force F. If the stone leaves with a velocity of 40m/s, the value of F is
- A. 4.0 x 102N
- B. 2.0 x 103N
- C. 4.0 x 103N
- D. 4.0 x 104N
A 2H inductor has negligible resistance and is connected to a 50/Ï€ Hz A.C. Supply. The reactance of the inductor is
- A. 200 Ω
- B. 50 Ω
- C. 100/π Ω
- D. 25/π Ω
I. Its velocity is constant II. No work is done on the body III. It has constant acceleration directed away from the centre IV. The centripetal force is directed towards the centre
Which combination of the above is true of a body moving with constant speed in a circular track?
- A. II and IV
- B. I and IV
- C. II and III
- D. I and III
A conductor of length 2m carries a current of 0.8A while kept in a magnetic field of magnetic flux density 0.5T. The maximum force acting on it is
- A. 0.2N
- B. 0.8N
- C. 3.2N
- D. 8.0N
in a pure semiconductor, the number of electrons in the conduction band is
- A. less than the number of holes in the valence band
- B. equal to the number of holes in the valence band
- C. greater than the number of holes in the valence band
- D. twice the number of holes in the valence band
A transverse wave is applied to a string whose mass per unit length is 3 x 10-2kgm-1. If the string is under a tension 12N, the speed of the propagation of the wave is
- A. 5 m/s
- B. 20 m/s
- C. 30 m/s
- D. 40 m/s