Physics Mock 2020

WASSCE style · Study mode

Physics Mock 2020

Question 1 of 50

Heat transfer through a vacuum takes place by

A. conduction B. radiation C. convection D. evaporation

Question 2 of 50

A wave of frequency 50 Hz has a wavelength of 4 m. Its speed is

A. 0.08 m/s B. 12.5 m/s C. 54 m/s D. 200 m/s

Question 3 of 50

A current of 2 A flows for 10 s. The charge passed is

A. 12 C B. 5 C C. 0.2 C D. 20 C

Question 4 of 50

The power of a lamp drawing 0.5 A from a 240 V supply is

A. 120 W B. 480 W C. 240.5 W D. 0.002 W

Question 5 of 50

A fuse protects a circuit by

A. melting when the current is too large B. storing charge C. increasing voltage D. reversing current

Question 6 of 50

An alpha particle is the same as a

A. helium nucleus B. electron C. proton D. neutron

Question 7 of 50

Which of these is a fundamental (base) quantity?

A. velocity B. mass C. force D. density

Question 8 of 50

Which of these is a derived quantity?

A. time B. length C. speed D. temperature

Question 9 of 50

The density of a block of mass 600 g and volume 200 cm³ is

A. 400 g/cm³ B. 0.33 g/cm³ C. 120,000 g/cm³ D. 3 g/cm³

Question 10 of 50

In which state of matter are particles closest together?

A. liquid B. solid C. gas D. plasma

Question 11 of 50

A force of 200 N acts on an area of 4 m². The pressure is

A. 204 Pa B. 800 Pa C. 50 Pa D. 0.02 Pa

Question 12 of 50

A body moving with constant velocity has an acceleration of

A. 10 m/s² B. zero C. 1 m/s² D. infinity

Question 13 of 50

The angle of incidence is 35°. The angle of reflection is

A. 145° B. 55° C. 70° D. 35°

Question 14 of 50

Total internal reflection is used in

A. plane mirrors B. optical fibres C. convex lenses D. loudspeakers

Question 15 of 50

Like charges

A. cancel out B. attract each other C. repel each other D. have no effect

Question 16 of 50

Which material is magnetic?

A. copper B. iron C. aluminium D. wood

Question 17 of 50

The region around a magnet where its force acts is its

A. domain B. pole C. magnetic field D. circuit

Question 18 of 50

The quantity of heat needed to raise 2 kg of water by 10 °C (c = 4,200 J/kg K) is

A. 840 J B. 8,400 J C. 42,000 J D. 84,000 J

Question 19 of 50

A vacuum flask reduces heat loss by conduction mainly through its

A. plastic cap only B. silvered surfaces C. vacuum between the walls D. outer case colour

Question 20 of 50

The bending of waves around obstacles is called

A. refraction B. reflection C. diffraction D. polarisation

Question 21 of 50

Three 6 Ω resistors are connected in parallel. Their effective resistance is

A. 6 Ω B. 18 Ω C. 2 Ω D. 3 Ω

Question 22 of 50

The half-life of a sample is 2 days. The fraction left after 6 days is

A. 1/8 B. 1/3 C. 1/6 D. 1/4

Question 23 of 50

In beta-minus decay, the atomic number of the nucleus

A. increases by 1 B. decreases by 2 C. stays the same D. decreases by 1

Question 24 of 50

For a projectile launched on level ground, the range is greatest at an angle of

A. 45° B. 30° C. 60° D. 90°

Question 25 of 50

The force that keeps a body moving in a circle is directed

A. towards the centre B. away from the centre C. along the tangent D. vertically upward

Question 26 of 50

The r.m.s. value of an alternating voltage with peak 100 V is about

A. 70.7 V B. 100 V C. 141 V D. 50 V

Question 27 of 50

A transformer with 100 primary turns and 500 secondary turns has a 20 V input. The output is

A. 100 V B. 4 V C. 20 V D. 520 V

Question 28 of 50

The power of a lens of focal length 0.5 m is

A. 2 D B. 0.5 D C. 5 D D. 50 D

Question 29 of 50

The pressure at a depth of 10 m in water (ρ = 1,000 kg/m³, g = 10 m/s²) due to the water is

A. 1,000,000 Pa B. 10,000 Pa C. 1,000 Pa D. 100,000 Pa

Question 30 of 50

A clinical thermometer has a constriction to

A. make it faster B. stop the mercury falling back before reading C. increase its range D. protect the bulb

Question 31 of 50

Alcohol is used in thermometers for very cold places because it

A. conducts electricity B. is opaque C. has a low freezing point D. has a high boiling point

Question 32 of 50

Light travelling from air into glass bends

A. not at all B. away from the normal C. towards the normal D. backwards

Question 33 of 50

A concave mirror is used as a

A. kaleidoscope only B. rear-view mirror in cars C. periscope D. shaving or make-up mirror

Question 34 of 50

The refractive index of glass in which light travels at 2 × 10⁸ m/s (c = 3 × 10⁸ m/s) is

A. 2 B. 0.67 C. 6 D. 1.5

Question 35 of 50

A polythene rod rubbed with wool becomes negatively charged because it

A. loses protons B. loses electrons C. gains protons D. gains electrons

Question 36 of 50

Sound of frequency 512 Hz travels in air at 340 m/s. Its wavelength is about

A. 1.5 m B. 0.66 m C. 174 m D. 6.6 m

Question 37 of 50

The apparent depth of a pool 2 m deep (n of water = 4/3) is

A. 2 m B. 2.67 m C. 1.5 m D. 1 m

Question 38 of 50

Convert 98.6 °F to Celsius.

A. 32 °C B. 35 °C C. 40 °C D. 37 °C

Question 39 of 50

The speed of light in water (n = 1.33) is about

A. 4 × 10⁸ m/s B. 3 × 10⁸ m/s C. 2.26 × 10⁸ m/s D. 1.33 × 10⁸ m/s

Question 40 of 50

The neutral point between two north poles facing each other is where

A. the field is strongest B. their fields cancel C. south poles form D. current flows

Question 41 of 50

Two cells of e.m.f. 1.5 V and internal resistance 0.5 Ω each are in series with a 2 Ω resistor. The current is

A. 3 A B. 0.5 A C. 1.5 A D. 1 A

Question 42 of 50

A galvanometer of resistance 50 Ω gives full-scale deflection at 1 mA. To convert it into a 10 V voltmeter, connect in series a resistor of

A. 10,000 Ω B. 9,950 Ω C. 50 Ω D. 0.005 Ω

Question 43 of 50

A galvanometer of resistance 50 Ω and full-scale current 1 mA is converted into a 1 A ammeter. The shunt needed is about

A. 5 Ω B. 50 Ω C. 0.05 Ω D. 0.5 Ω

Question 44 of 50

The de Broglie wavelength of a particle increases when its

A. energy increases B. speed increases C. mass increases D. momentum decreases

Question 45 of 50

A radioactive count falls from 640 to 40 counts/min in 20 minutes. The half-life is

A. 10 minutes B. 5 minutes C. 4 minutes D. 20 minutes

Question 46 of 50

A car moving at 72 km/h brakes uniformly to rest in 5 s. The stopping distance is

A. 25 m B. 100 m C. 50 m D. 180 m

Question 47 of 50

A U-tube contains water and oil. A 10 cm column of oil balances 8 cm of water. The density of oil is (water 1,000 kg/m³)

A. 1,250 kg/m³ B. 800 kg/m³ C. 1,000 kg/m³ D. 80 kg/m³

Question 48 of 50

A resistance thermometer reads 10 Ω at 0 °C and 14 Ω at 100 °C. At 12.5 Ω the temperature is

A. 50 °C B. 25 °C C. 62.5 °C D. 75 °C

Question 49 of 50

Light of wavelength 600 nm in air enters glass (n = 1.5). Its wavelength in glass is

A. 900 nm B. 400 nm C. 600 nm D. 300 nm

Question 50 of 50

A charge of 5 μC experiences a force of 0.02 N. The electric field strength is

A. 100 N/C B. 0.0001 N/C C. 400 N/C D. 4,000 N/C

Questions written by OtisamLMS in the style of the WASSCE. They are not WAEC past questions.