Question 286:

• JAMB 1983

the image above shows an inverted U-tube with the open end, O of one limb below the level, W of water in the tank, in order that water should begin to flow from the tank it is is necessary that

A. The U-tube is completely filled with water and that P should be higher that W
B. P should be lower than O and W
C. P should be lower than W and O should reach the botton of the table
D. The U-tube is completely filled with water and that P should be lower that W

Question 287:

• JAMB 1983

Four resistors R1,R2,R3 and R4 are connected in series as shown above, V1,V2,V3 are voltmeters connected as indicated above. Which of the following relations is correct??

A. V1 = V3 =V2/2
B. V1 = 2V2 = V3
C. V1=1/2V3 =V3
D. V2 - V1 = V3

Question 288:

• JAMB 1983

In the Figure above, QR is a vertical conductor and the current I flows from R to Q, P is a point on the horizontal plane and is to the south of the wire. The direction of the magnetic field at P due to the current is

A. Upward
B. North
C. South
D. West
E. East

Question 289:

• JAMB 1983

Each of the figures in the diagram above represent two current carrying conductors situated close to each other. In which two diagrams, are the forces between the two wires attractive

A. I and V
B. I and II
C. II and IV
D. II and V
E. III and IV

Question 290:

• JAMB 1983

Which of the following figures gives the correct resultant R of two vectors P and Q?

A. I
B. II
C. III
D. IV
E. V