5173707
Flashcards by pranathi_shekar, updated more than 1 year ago
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Created by pranathi_shekar
about 5 years ago
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Description
| Question | Answer |
| Energy cannot be created or ________. It can only be ___________ from one form to another. (law of conservation of energy) | destroyed transformed |
| Where does a kettle get its energy from? What is the useful energy from a kettle? | Electric Heat |
| Current and Voltage is measured in ...... | Ampere (Amps) Volts |
| What are the advantages of using a parallel circuit instead of a series circuit? | If a wire in a parallel circuit breaks the component (bulb) will still work but it wouldn't in a series circuit. |
| What is a fuse and what how does it work? | A fuse is a safety device that prevents electrocution. When there is too much current flowing the fuse breaks down and melts, disconnecting the circuit. |
| Which of the following three fruits generates the most electricity naturally and why? Potato Lemon Orange | Lemon, because it has the most citric liquid. |
| State 4 properties of metals. | Any 4 from: Strong Ductile Malleable Solid Shiny when clean High melting and boiling points Good conductor of heat and electricity Dense Sonorous |
| State 3 uses of metals | Mercury - thermometers Copper - copper wire for electricity Titanium - airplane bodies |
| The squeaky pop test is a test for what gas? | Hydrogen |
| What is needed for rusting to take place? | Water and Oxygen |
| The process of rusting is called oxidation while the chemical name for rusting is __________ ________ | iron oxide |
| State the 3 ways in which rusting can be prevented. | Greasing or oiling Plating Painting |
| Metal + Acid = ________ + __________ | Salt Hydrogen |
| Sodium + sulfuric acid = ___ + ___ | Sodium sulfate Hydrogen |
| State the reactivity series from potassium to gold. | Potassium Sodium Calcium Magnesium Aluminium Zinc Iron Lead Copper Silver Gold |
| Copper compounds are _____ | blue |
| Iron salts are pale green or _____ | brown |
| Aluminium salts are white or colorless while calcium salts are _____ | white |
| Do most metal carbonates dissolve in water? | Yes, they do. |
| Metal carbonate + acid = _______ + _______ + ________ | Salt Carbon dioxide Water |
| Define bases. | Metal oxides, hydroxides and carbonates that are all alkali. |
| Copper oxide + HCL = Copper hydroxide + HCL = Copper carbonate + HCL = | Copper chloride + water Copper chloride + water Copper chloride + water + carbon dioxide |
| In what substance are Nitrogen, Potassium and Phosphate in? | Fertilizers |
| How can you make large copper sulfate crystals? | By suspension. Suspend a small copper sulfate crystal in a concentrated copper II sulfate solution. |
| Which salt is formed from the reaction of calcium with nitric acid? | Calcium nitrate |
| Which gas is formed when a metal carbonate reacts with acid? | carbon dioxide |
| What is the most reactive metal in the group one metals in the periodic table? | Francium |
| What is this test for? "Put a burning splint into a tube of the gas ( the gas will explode with a squeaky pop) | Hydrogen gas |
| Which of these is NOT a sign that a reaction has taken place? a. the substance catches fire b. the substance has changed from a solid to a liquid c. A gas is given off d. There is an explosion | b |
| In an experiment involving metals and its conduction of electricity which metals would have the greatest voltage? a. copper & copper b. zinc & copper c. zinc & zinc | b |
| What would you get if copper sulfate and magnesium were reacted together (displacement reaction) and explain? | magnesium sulfate and copper Magnesium will displace copper from its sulfate since it is more reactive than copper. |
| Iron sulfate + copper = | NO REACTION |
| Define exothermic and endothermic reactions. | Exothermic reaction - when heat is released Endothermic reaction - when heat is absorbed |
| What is more reactive, copper or gold? | Copper |
| Complete combustion of carbon is when carbon is burnt in an excess supply of oxygen producing carbon dioxide and more energy. What is incomplete combustion of carbon? | When carbon is burnt in a limited supply of oxygen producing carbon monoxide and less energy. |
| If I burn a metal in air will its mass change? If so will it decrease or increase? | Yes the mass will change and it will increase. |
| What is combustion? | When an element burns in air (to give an oxide). |
| What needs to happen for this reaction to take place? Aluminium + iron oxide = Aluminium oxide + iron | It needs to be heated |
| When magnesium is burnt, what happens? | There will be a big white dazzling flame and the magnesium remains will turn white |
| What sort of reaction is this? Potassium + oxygen = Potassium oxide | Oxidation |
| Iron is unreactive in ________ and ________ but reacts in _______ | Water or Air in any order Acid |
| Distance is = ? Speed is = ? Time is = ? | Speed * time Distance/time Distance/speed |
| How long would it take a person to walk 10km if their average speed is 5.4km/h? | 10/5.4 = 1.85 hours =1.85*60 =111 minutes |
| A car is travelling at a constant speed. Compare the forward and the backward forces. | They would be the same. |
| Give a more scientific term for increasing speed and decreasing speed. | acceleration deceleration |
| What is the formula for acceleration/deceleration (also include the words final and initial speed/time)? | = final speed - initial speed ___________________________ final time - initial speed |
| A person first travels for 4 seconds, steadily increasing their speed to 6 m/s from 0 m/s. Then they maintain a constant speed for the next 6 seconds. After they steadily decrease their speed to rest in the last 4 seconds. Calculate the deceleration and acceleration rate (show working). | Acceleration = 6-0/ 4-0 = 1.5 m/s (squared) deceleration = 0-6/ 14-10 = 1.5 m/s (squared) |
| When there is a balanced force from the left and the right of an object, the object is either at _____ or maintains a _________ speed. | rest constant |
| A bicyclist streamlines her body. Why? | Because then there is less air resistance acting on her from in front so the force pushing forward would be greater. |
| A man on a parachute lands safely. Why? | Because the parachute has a large surface area, there is a stronger air resistance force but the gravitational force however is stronger. |
| Air resistance depends on the size, the _____ and the _____. | Shape Speed |
| Who discovered force? (Newtons) | Issac Newton |
| The Normal force (force applied at 90 degrees) per unit area is the definition of what term? | Pressure |
| Pressure = ? Force = ? Area = ? | Force/Area Pressure*Area Force/Pressure |
| Pascal is = ? | Newtons/meter squared |
| Weight, a force, = ? | mass*gravity |
| 10m/s squared is = what force? | Gravity |
| The ________ surface area the higher the pressure. Max pressure = Force/min Area Min pressure = Force/max Area | smaller |
| Why do knives have a sharp edge? | Because they are used to cut through something and if they have a small surface area at their point then less force can be applied and there will still be a high pressure. |
| Why does a balloon expand (force)? | When air is blown into a balloon a force is exerted on the molecules causing them to push the balloon walls thus forcing the balloon to expand. |
| The ________ the altitude the ________ the atmospheric pressure. | lower - higher OR higher - lower |
| Why do tractors have large tyres? | This helps because the tractor would not get stuck in the soil since there is less pressure applied onto the soil because of the large surface area of the tyres |
| Does pressure in liquids increase or decrease with depth? | Increases with depth |
| When I put a beaker on a strip of water nothing really happens but when I put a burning paper in the beaker then put it on a strip of water, the water outside of the beaker pushes the water inside the beaker. Why? | At first the pressure is the same in and out the beaker but when the burning paper is put in the beaker oxygen is being used up thus creating a lower pressure inside the beaker and a higher pressure outside. The higher pressure outside pushes the water into the beaker. |
| Define a moment | a turning effect of a force at a fixed point (pivot) |
| The larger the perpendicular distance form the pivot point and the bigger the force the ______ the turning point. | larger |
| Moment of a force = ? Unit for moment = ? | Force * perpendicular distance form pivot Newton meter (Nm) |
| A large force * a small distance = a ________ force * a _________ distance | small large |
| The force is 2N The perpendicular distance is 0.4m. What is the moment? | 2*0.4 = 0.8Nm |
| Clockwise moment = _________ moment Balanced or not moving object | Anti-clockwise |
| The larger the perpendicular distance from the pivot, the _____ force needed. | less |
| Why should you grip the handle bars of a bicycle at the ends? | Because that would mean less force will be needed to turn or twist since the perpendicular distance is large so less force needed. |
| Where is the center of gravity for uniform objects like a meter ruler? | The center of the body |
| What should I do if I want to stabilize an object? State the two factors. | Put the object on a large surface area and make sure the center of gravity of the object is closer to the ground. |
| How can an object be in an unstable equilibrium? | When its center of mass / gravity is directly above the pivot point. |
| Pressure in _________ = depth * density * gravity | liquids |
| When a car passes by, a person was pushed slightly towards the car. Why? | A car runs by the engine which uses oxygen, so when the car passes by the person the oxygen on one side of him/her is taken in creating a low pressure thus making the higher pressure on his/her other side push the person towards the car. |
| What does hydraulic fluid do? | Hydraulic fluid is used in car brakes and multiplies the force and area but the pressure will be the same as the beginning. e,g 10/2 = 5 ALSO 1000/200 = 5 |