Physics 1997 Jamb Past Questions and Answers

Question 11 :

• JAMB 1997

An electric water pump rate 1.5 kW, lifts 200kg of water through a vertical height of 6 meters in 10 seconds. What is the efficiency of the pump? [g = 10ms-2, neglecting air resistance]

A. 90.0%
B. 85.0%
C. 80.0%
D. 65.0%

Question 12 :

• JAMB 1997

A load of 20N on a wire of cross-sectional area 8 x 10^-7m², produces an extension of 10m². calculate Young's modulus for the material of the wire if its length is 3m

A. 7.0 x 10¹¹Nm^-2
B. 7.5 x 10¹¹Nm^-2
C. 8.5 x 10¹¹Nm^-2
D. 9.0 x 10¹¹Nm^-2

Question 13 :

• JAMB 1997

A cube of sides 0.1m hangs freely from a string. What is the upthrust on the cube when totally immersed in water? [density of water is 1000kgm^-2, g = 10ms^-2]

A. 1000 N
B. 700 N
C. 110 N
D. 10 N

Question 14 :

• JAMB 1997

A piece of wire gauze can be made to lie on water because

A. The wire guaze is less dense than water
B. The water molecules repels the wire guaze upwards
C. The water surface has the effect of an elastic thin skin
D. Of the cohensive forces between the water and the wire guaze molecules

Question 15 :

• JAMB 1997

A liquid of mass 1.0 x 10³kg fills a rectangular tank of length 2.5m and width 2.0m. If the tank is 4m high, what is the pressure at the middle of the tank?[g = 10ms^-2]

A. 1.0 x 10⁴Nm^-2
B. 2.0 x 10³Nm^-2
C. 1.5 x 10³Nm^-2
D. 1.0 x 10³Nm^-2