- A boy 150 cm tall forms a shadow of length 200 cm. A tree nearby forms a shadow of length 800 cm as shown in the figure.
calculate the height of the tree. (3 marks)
2. In an experiment to estimate the height of a tree using its shadow, a ruler of height 100cm is placed next to the tree. If the ruler and the tree forms shadows of 150cm and 750cm respectively. Calculate the height h of the tree. (3 marks)
3. Figure below shows the position of a students eye while measuring the length of a wooden block using a metre rule.
Determine the length of the block as viewed by the student.
4. Explain how parallax error can affect length measurements. Suggest methods to minimize parallax error when using measuring instruments.
5. A student measures the length of a table using a meter scale and records it as 1.20 meters. Another student measures the same table using a vernier caliper and records it as 1.21 meters. If the actual length of the table is 1.22 meters, calculate the percentage error in each measurement.
6. A cylindrical rod is measured using a micrometer screw gauge. The main scale reading is 2.0 cm, and the thimble scale reading is 0.28 mm. Calculate the measured length of the rod in millimeters.
7. A student measures the length of a wire using a meter scale and reads the value as 50.3 cm. However, the zero mark of the scale is slightly shifted. If the zero error is found to be -0.2 cm, what is the correct length of the wire?
8. What is the SI unit of length?
(a) Meter
(b) Kilogram
(c) Second
(d) Kelvin
b) Which of the following instruments is used to measure length with high precision?
(a) Ruler
(b) Vernier caliper
(c) Measuring tape
(d) Stopwatch
Related Topics
- Physical quantities
- Measuring with a ruler
- Physical Quantities
- Length
- Reading a meter rule
- Measuring with a meter rule