1998 - JAMB Physics Past Questions and Answers - page 4
A man wears convex lens glasses of focal length 40cm in order to correct his eye defect. instead of the optimum 25cm, his least distance of distinct vision is
Which of the following are true about the infra-red radiation? i. it is invisible ii. it is called heat ray iii. its frequency is higher than that of blue light iv. it travels as a transverse wave
The force of repulsion between two point positive charges 5(\mu)C and 8(\mu)C separated at a distance of 0.02 map art is. [(\frac{1}{4{\pi}{\varepsilon}_o}) = 9 x 109Nm2C-2]
An ebonite rod rubbed with fur attracts a glass rod rubbed with silk because
Which of the following can be used to reduce local action in a Laclanche cell?
Find the work done in moving a 2 C charge between two points X and Y in an electric field if the potential difference is 100 volts
A parallel plate capacitor has a common plate area of 5 x 10-8m2 and plate separation of 2 x 103m, Assuming free space, What is the capacitance? [(\varepsilon)o = 9.0 X 10-12C2N-1m-2]
The iron core of an induction coil is made from bundles of wire so as to
Electricity is supplied to a school along a cable of total resistance 0.5(\Omega) with the maximum current drawn from the mains as 100A. The maximum energy dissipated as heat for 1 hr is
A transformer which can produce 8V from a 240v a.c. supply, has an efficiency of 80%. If the current in the secondary coil is 15A, calculate the current in the primary coil.