The period of a wave is 0.02 second. Calculate its wavelength if its speed is 330 ms^-1

• A. 6.6m
• B. 5.0m
• C. 4.0m
• D. 3.3m

The general definition of elastic modulus is

• A. \(\frac{stress}{strain}\)
• B. \(\frac{strain}{stress}\)
• C. \(stress \times strain\)
• D. \(\sqrt{\frac{stress}{strain}}\)

A semiconductor diode is used in rectifying alternating current into direct current mainly because it

• A. allows current to flow in either direction
• B. is non-linear
• C. offers a high input resistance
• D. allows current to flow only in one direction

A body of mass 100g moving with a velocity of 10.0ms-1 collides with a wall. If after collision, it moves with a velocity of 2.0ms-1 in the opposite direction, calculate the change in momentum.

• A. 0.8Ns
• B. 1.2Ns
• C. 12.0Ns
• D. 80.0Ns

(a)(i) Name and explain the common defects of a primary cell.

(ii) State two advantages of a secondary cell over a primary cell.

(b) Draw a labelled diagram to show the essential parts of a dry leclanche cell.

(c)(i) Explain why six accumulators each of e.m.f 2V connected in series can be used to start the engine of a car whereas eight dry cells each of e.m.f 1.5 V connected in series cannot be used.

(ii) Name the materials used for the positive terminal, the negative terminal and the electrolyte in a

I. leclanche cell;

II. charged lead acid accumulator.

Which of the following instruments gives a pure note when sounded?

• A. talking drum
• B. siren
• C. tunning fork
• D. guitar

A bridge made of steel is 600m long. What is the daily variation in its length if the night-time and daytime temperatures are 10°C and 35°C respectively. The linear expansivity of steel is 0.000012C\(^{-1}\).

• A. 0.18cm
• B. 1.80cm
• C. 18.00cm
• D. 1800cm

What is a projectile? Give four examples of projectiles in everyday life

A light of energy 5eV falls on a metal and the electrons with a maximum kinetic energy of 2eV are ejected. The work function of the metal is

• A. 0.4eV
• B. 2.5eV
• C. 3.0eV
• D. 7.0eV

A generator manufacturing company accidentally made an AC generator instead of a DC generator. To fix this error,

• A. the magnetic field needs to be made stronger
• B. the split rings should be replaced with slip rings
• C. the number of turns of the armature coil needs to be decreased
• D. the slip rings should be replaced with split rings