1. State the properties of the image formed by a plane mirror Upright Image size equals object size Virtual Image distance equals object distance Laterally inverted. 2. State one advantage of using a plane mirror in optical testing. When a plane mirror is used, the image of the optical test card will be at a …
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Chapter 11 – Thermal Properties of Matter
1. When thermal energy is supplied to melt a solid, the temperature remained constant during the melting point. Explain what happened to the heat energy supplied. During melting, thermal energy absorbed is used to break the intermolecular bonds between the particles, resulting in increase in potential energy of the substance. Thermal energy is not used …
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Chapter 10 – Transfer of Thermal Energy
1. Describe, in molecular terms, how energy transfer occurs in solids. When a substance (object) is heated at one end, the particles at the region gains thermal energy and vibrate faster. These molecules collide with the less energetic neighbouring particles and transfer KE to them. In this way, thermal energy is transferred along the entire …
Chapter 9 – Kinetic Model of Matter
1. Describe how you would demonstrate Brownian motion of smoke particles in the air. State and explain the observations. Direct light into the side of an enclosed smoke cell/chamber. View the smoke particles from the top, under a microscope. Bright specks of smokes will be seen as light reflects from the smoke particles The bright …
Chapter 8 – Temperature
1. *State the thermometric property that defines the temperature scale in a liquid-in-glass thermometer. Volume of a fixed mass of liquid. 2. *Describe how you would calibrate an unmarked mercury-in-glass thermometer. Place the bulb of the unmarked thermometer in pure melting ice at a pressure of 1 atmosphere. When the mercury level is steady, mark …
Chapter 7 – Pressure
1. Explain why a sharp knife cuts better than a blunt one. A sharp knife has a smaller area of contact with the object to be cut. For the same force exerted, a smaller area gives greater pressure as indicated by Pressure = Force / Area 2. *Explain why the height of the mercury in …
Chapter 6 – Work, Energy and Power
1. Describe the energy changes that take place when a ball is being thrown upwards by a hand. (Neglecting air resistance) As the ball just leaves the hand, it possesses maximum amount of KE. Its GPE is zero due to the zero height from the hand. As it moves upwards, it loses speed. The KE …
Chapter 5 – Moments
1. Explain briefly how the use of a screwdriver enables the lid of a paint can to be opened with a relative small force. Moment is the product of force and the perpendicular distance between the force and the pivot. When a force is applied at the far end of the screw driver, the perpendicular …
Chapter 4 – Mass, Weight and Density
1. Explain why a beam balance will give the same value of mass at different places for the same object. Bean balance measures the mass of the object and mass is constant and does not change from place to place. 2. Explain why a spring balance may give different readings at different places when weighing …
Chapter 3 – Forces
1. Describe ways in which a force might change the motion of a body. A force is may make o stationary bodies move. o moving bodies speed up, slow down or stop. o moving bodies change direction. 2. Describe how an object released from rest (subjected to air resistance) will eventually fall …