Chapter 1 Practice Paper: Forces and Energy — mark scheme (print)

QuizQuipPractice Series

QQ/S2SCI/CH1

Secondary 2 · Lower Secondary Science (G2 / G3)

Mark scheme

Forces and Energy

Chapter 1 Practice Paper · Maximum mark: 30

Notes for markers

Award one mark for each point marked [1], up to the marks shown for the part.
Accept answers worded differently that show the same understanding.
Units are required where the answer line shows one. ecf: allow an error carried forward.

Section A: Multiple-choice questions[10 marks]

Question	Answer
1	AGravity is a non-contact force. Friction and a push need contact.	1
2	CForce is measured in newtons with a force meter. The joule is the unit of energy.	1
3	BPressure = force ÷ area = 200 ÷ 40 = 5 N/cm².	1
4	DMass does not change if the object is moved to a place with different gravity. Weight does.	1
5	AThe same force on a smaller area gives a higher pressure, so the point enters the board.	1
6	CThe cells transfer energy as light and heat. Energy is measured in joules and is not destroyed.	1
7	DOn Earth, each kilogram weighs about 10 N, so the hammer weighs about 40 N. The mass stays 4 kg.	1
8	BFriction acts where surfaces touch and opposes sliding.	1
9	AKinetic energy is the energy of a moving object.	1
10	CThe energy is transferred, not created. Burning the fuel has an environmental cost.	1

Section B: Structured questions[20 marks]

Question	Answer and marking points	Marks
1(a)	Statue A: 200 ÷ 40 = 5 N/cm². Statue B: 200 ÷ 10 = 20 N/cm². 5 N/cm² [1] 20 N/cm² [1] Both values are needed. Working may be implied by a correct value.	2
1(b)	Statue B, because the same weight acts on a smaller base, so the pressure is higher. Statue B [1] Higher pressure / smaller area [1]	2
1(c)	The newton (N). Newton / N [1]	1
	Total for Question 1	5
2(a)	6 × 10 = 60 N 6 × 10 [1] 60 N [1]	2
2(b)	6 kg is the mass, the amount of matter. 60 N is the weight, the gravitational force on that matter. 6 kg is the mass / amount of matter [1] 60 N is the weight / gravitational force [1]	2
2(c)	A force meter. Force meter / newton meter [1]	1
	Total for Question 2	5
3(a)	Electrical energy is transferred as light. Heat is also produced. Electrical energy to light [1] Heat is also produced [1]	2
3(b)	The kinetic energy is transferred, often as heat to the ball and the ground. Energy is not destroyed. The energy is transferred, often as heat [1] Energy is not destroyed [1]	2
3(c)	The joule (J). Joule / J [1]	1
	Total for Question 3	5
4(a)	Sucking reduces the pressure inside the pipette. The higher atmospheric pressure on the water pushes the liquid up. Pressure inside the pipette is reduced [1] Atmospheric pressure pushes the liquid up [1]	2
4(b)	Benefit: it provides heat for cooking. Problem: it releases smoke or carbon dioxide. A benefit, such as heat for cooking [1] A problem, such as smoke or carbon dioxide [1]	2
4(c)	A non-contact force. [1]	1
	Total for Question 4	5

— End of mark scheme —