# Jamb past questions

## A 500kg car which was initially at rest travelled with an acceleration of 5m/s², its kinetic energy after 4 seconds was

Jamb 1979 A 500kg car which was initially at rest travelled with an acceleration of 5m/s², its kinetic energy after 4 seconds was A. 10⁵J B. 2.5 x 10³J, C. 2 x 10³J D. 5 x 10³J E. 5 x 10⁵J  ANSWER: Option A EXPLANATION:  KE = ½mv² Since v = u + at KE …

## Two resistors R1 and R2 are connected in parallel, R2 being greater than R1. The combined resistance is

Jamb 1978 Two resistors R1 and R2 are connected in parallel, R2 being greater than R1. The combined resistance is  A. less than R1 B. greater than R2 C. the sum of R1 and R2 D. the difference of R2 and R1 E. greater than R1 but less than R2 ANSWER: Option A EXPLANATION: Simple! …

## Which of the following is true for the image formed by a convex mirror

Jamb 1978 Which of the following is true for the image formed by a convex mirror? 1. The image is always virtual II. The image is always erect II. The image lies between pole and focus IV. The image is never magnified V. The focal length is negative A. I only B. I and II …

## If in a simple pendulum experiment the length of the inextensible string is increased by a factor of four, its period is increased by a factor of

Jamb 1979 If in a simple pendulum experiment the length of the inextensible string is increased by a factor of four, its period is increased by a factor of A. 4 B. π/2 C. 1/4 D. 2π E. 2 ANSWER: Option E EXPLANATION: for simple pendulum; T = 2π√(L/g) Where; T is the Tension L …

## The density of 400cm³ of palm oil was 0.9 g/cm³ before frying. If the density of the oil was 0.6 g/cm³ …..

Jamb 1979 The density of 400cm³ of palm oil was 0.9 g/cm³ before frying. If the density of the oil was 0.6 g/cm³ after frying, assuming no loss of oil due to spilling, its new volume was A. 360cm³ B. 600cm³ C. 240cm³ D. 800cm³ E. 450cm³ ANSWER: Option B EXPLANATION: since Density = mass/volume …

## The density of a solid is defined as the

Jamb 1978 The density of a solid is defined as the A. mass of the solid compared to the mass of an equal volume of water B. amount of water displaced when a unit mass of the solid is immersed in it C. weight per unit volume of the solid D. volume per unit mass …

## If NEPA charges 5k per kWh, what is the cost of operating for 24 hours a lamp requiring 1A on a 200V line?

Jamb 1978 If NEPA charges 5k per kWh, what is the cost of operating for 24 hours a lamp requiring 1A on a 200V line?  A. 24K  B. 55K  C. 40K  D. 26K  E. 32K.  ANSWER: Option A EXPLANATION: refer to the image below!  Previous       Next Or click here to choose!  Of …

## The following are some units l. NS ll. Nm lll. N/m² lV. J/°K V. J/kg What are the units of latent heat?

Jamb 1978 The following are some units  l. NS ll. Nm lll. N/m² lV. J/°K V. J/kg What are the units of latent heat? A. I B. II C. III D. IV E. V ANSWER: Option  E EXPLANATION:  From Q = mL L = Q/m  Q is measured in Joule m is measured in kg …

## In order to convert a galvanometer into an ammeter

Jamb 1978 In order to convert a galvanometer into an ammeter  A. a low resistance shunt is connected in parallel  B. a low resistance shunt is connected in series  C. a medium resistance shunt is connected in series  D. a high resistance shunt is connected in parallel  E. a high resistance shunt is connected in …

## Which of the following statements defines correctly the efficiency of a machine

Jamb 1979 Which of the following statements defines correctly the efficiency of a machine? A. The load carried by the machine divided by effort required in carrying the load B. The distance moved by the load divided by the distance moved by the effort C. The useful work done by the machine divided by the …