Physics Exam Answers and Explanations
Classified in Physics
Written at on 
English with a size of 2.49 KB.
A/C/B/D/A/B/B/B/B/C/A/B/A/D/A/C/C/C/A/B/D/A/A/B/B/A/C/D/B/D
1. Stopwatch Accuracy
a) Stopwatch
b) To have more accuracy
c) i) 3rd
ii) (3.93 + 4.07 + 3.99) / 3 = 11.99 / 3 = 4
iii) 4 / 10 = 0.40
2. Water Speed Measurement
a) First, measure the distance between bridge X and bridge Y. Then, place the stick in the water at bridge X and time how long it takes to reach bridge Y. Calculate the speed by dividing the distance by the time. Repeat this process at least three times. Add all the results together and divide by three to get the average speed.
b) 2nd box
3. Acceleration and Force
a) i) 24 / 60 = 0.4 m/s2
ii) 7.5 × 105 × 0.4 = 300,000 N
b) Speeding up / Slowing down / Steady speed / At rest
4. Resultant Force and Density
a) i) 280 - 250 = 30 N
ii) Up
b) First, weigh the link. Then, fill a cylinder with water and note the volume. Place the link inside and calculate the volume increase. That will be the volume of the link. Then, divide the mass by that volume to find the density.
Page: 22
5. Paper Marks and Distance Calculation
a) i) Mark on paper
ii) Increases / Stays the same; Stays the same / Decreases
b) (1500 × 0.054) / 2 = 40.5 m
6. Wave Properties
a) i) Compression
ii) Rarefaction
b) *Particles are* closer together at compression and further apart at rarefaction. / Amplitude changes. / Loudness does not affect wavelength.
7. Energy Transformations
a) It starts with gravitational potential energy and then *converts to* kinetic energy.
d) Nuclear and geothermal
8. Solar Panel Materials
Black Painted Surfaces: Black surfaces absorb more sunlight and convert it into heat more efficiently than lighter surfaces. This increases the temperature of the water circulating through the copper pipes.
Copper Pipes: Copper efficiently transfers heat from the absorbed sunlight to the water flowing through the pipes, raising its temperature effectively.
Insulating Material: Insulation minimizes heat loss, retaining more of the heat absorbed from sunlight and maintaining a higher water temperature as it flows through the solar panel.
9. Hooke's Law
a) The extension of a spring is in proportion to the force applied to it (Hooke's Law).
b) i) It is a straight line through the origin.
ii) 50 / 20 = 2.5 N/mm