1 Diagram 1 shows information about a light bulb displayed in a light shop. | | | |---|---| | Voltage required | 230 V | | Colour | White | | Power | 40 W | | Luminous intensity | 7543 cd | | Illuminated surface area | 0.88 m² | Which of the details given in Diagram 1 is a base quantity? flag bookmark A Power B Voltage required C Luminous intensity D Illuminated surface area T4 Chapter 1.1 Physical Quantities Luminous intensity (unit candela, cd) is one of the seven base quantities. Power, voltage and area are derived quantities.
2 Diagram 2 shows a graph of R against 1/A. Which statement is correct? flag bookmark A R is directly proportional to A. B R is inversely proportional to 1/A. C The unit for the gradient of the graph is kΩ mm². D The value of the gradient is given by 0.0005/5. T4 Chapter 1.2 Scientific Investigation Gradient = R ÷ (1/A), so its unit is kΩ ÷ mm⁻² = kΩ mm². The straight line through the origin shows R is directly proportional to 1/A (inversely proportional to A), and the gradient is 5/0.0005, not 0.0005/5.
3 Which tape chart shows the motion of an object with uniform acceleration? flag bookmark A B C D T4 Chapter 2.2 Linear Motion Graphs Each strip is the distance moved in equal time intervals. In chart B the strip lengths increase by the same amount each time, so the velocity increases uniformly: uniform acceleration. A is uniform velocity, C increases unevenly and D shows deceleration.
4 Diagram 3 shows a cyclist moving up a hill with uniform deceleration. The cyclist then goes down the hill with uniform acceleration. Which velocity-time graph shows the motion of the bicycle? flag bookmark A B C D T4 Chapter 2.2 Linear Motion Graphs Going up, the velocity decreases at a constant rate (straight line sloping down); going down, it increases at a constant rate (straight line sloping up). This V shape is graph B.
5 Diagram 4 shows a brick falling from a tall building at a construction site. What happens to the velocity and acceleration of the brick as it falls to the ground? | | Velocity | Acceleration | |---|---|---| | A | Constant | Constant | | B | Increasing uniformly | Constant | | C | Constant | Increasing | | D | Increasing uniformly | Increasing | flag bookmark A Constant – Constant B Increasing uniformly – Constant C Constant – Increasing D Increasing uniformly – Increasing T4 Chapter 2.3 Free Fall Motion The brick is in free fall, so its acceleration is the constant gravitational acceleration g, and its velocity increases uniformly.
6 Most supertankers turn off their engines about 25 km away from the dock because flag bookmark A the impulsive force is small B the inertia of the cargo ship is large C the time of impact is long D the impulse of the cargo ship is big T4 Chapter 2.4 Inertia A loaded supertanker has a very large mass, so it has very large inertia and keeps moving for a long distance. It is very hard to stop, so the engines must be turned off far from the dock.
7 Diagram 5 shows a baseball player taking a follow-through action to hit the ball. This action is to flag bookmark A increase the impulsive force B reduce the time of impact C increase the distance of the ball after being hit D reduce the change of momentum T4 Chapter 2.7 Impulse and Impulsive Force Following through keeps the bat in contact with the ball for a longer time, so the impulse (F × t) and the change in momentum of the ball are larger. The ball leaves with a higher velocity and travels further.
8 Diagram 6 shows a firefighter holding a water hose firmly so that the recoil of the hose can be overcome as the water is ejected from the hose. Which physics law can explain this situation? flag bookmark A Newton's First Law of Motion B Newton's Second Law of Motion C Newton's Third Law of Motion T4 Chapter 2.6 Force The hose pushes the water forward (action) and the water pushes the hose backward with an equal and opposite force (reaction). This is Newton's third law.
9 It is easier for an astronaut to walk on the surface of the Moon compared to walking on the Earth because flag bookmark A the centripetal force is low B the mass of the astronaut is less C the weight of the astronaut is less D the strength of the gravitational field of the Moon is high T4 Chapter 2.8 Weight The Moon's gravitational field strength is about one sixth of the Earth's, so the astronaut's weight (W = mg) is much less, although the mass is the same.
10 "The gravitational force between two bodies is directly proportional to the product of the masses of both bodies and inversely proportional to the square of the distance between the centres of the two bodies." Which law is described by the statement above? flag bookmark A Kepler's Second Law B Kepler's Third Law C Newton's Second Law of Motion D Newton's Universal Law of Gravitation T4 Chapter 3.1 Newton's Universal Law of Gravitation This is the statement of Newton's universal law of gravitation, F = GMm/r².