North Vista 5105 Prelim 4NA 2024 MS

1 Secondary 4NA Preliminary Examination Paper 2024 Marking Scheme Paper 1 1 C Weight is a force and forces have direction in addition to magnitude. 2 C The radius of the Earth is 6 378 000m 3 C distance travelled = area under graph = ½ x base x height = ½ x 3 x 9 = 13.5m 4 B Gravitational acceleration is constant. Since there is acceleration, the velocity must be increasing. 5 B The object does not move to the left or right → forces to the left and to the right must be equal and opposite to each other. Object accelerates downwards → force acting down must be greater than force acting up. 6 A Mass is measured with a beam balance or an electronic balance 7 D Least density → lowest amount of mass packed into the same volume Thus, to have the same mass, an object with a lower density must be bigger than another object with a larger density 8 A Formula for pressure 9 A Molecules in both gas and liquid are able to move freely but the force of attraction between molecules in a gas is weaker than that between molecules in a liquid 10 A Gas has no fixed volume and shape 11 B With the saucer, the air above the coffee cannot circulate 12 A Definition of wavefront 13 C Amplitude is the largest displacement from rest position 14 B Gamma radiation kills cells 15 A Q = It = 4 x 30 = 120C 16 B Ammeter connected in series while voltmeter connect in parallel to the lamp 17 C Current flowing out of battery = current flowing into battery 18 B Think reverse alphabetical order clockwise (Green and Yellow, Brown, Blue) 19 D Fuse and switch ha ve to be placed along the live wire (between live terminal and the appliance) 20 D gamma radiation is an EM Wave, beta is an electron and alpha is a helium nucleus, thus gamma is the most penetrative

2 Paper 2 Section A Qn Solution Marks 1 a 3.0 x 108m/s [1] b v = fλ 3.0 x 108 = f x 920 x 10–9 f = 3.26 x 1014Hz or 3.3 x 1014Hz [1] [1] c radiowave transmission of radio signals , transmission of television signals , RFID tags, radio telescope for radio astronomy OR microwaves transmission of mobile phone signals, satellite communication, heating of food in microwave ovens, radar [1] [1] 2 a a = (v – u)/t = (28 – 0)/3.5 = 8.0m/s2 [1] [1] b F = ma = 620 x 8 = 4960N [1] 3 a [1] time/min 100 10 20 30 40 50 60 80 0 20 40 60 distance /km

3 b Working with points chosen clearly shown on graph. Gradient correctly calculated to 3 significant figures. [1] [1] 4 statement true/false [3] The SI unit for density is g/cm3. false All electromagnetic waves are transverse waves. true When water freezes into ice, the temperature remains unchanged because the inte