Please quick help:- Grade 9 Why do physicists work in SI units?

What are the SI base units and their symbols for length, mass, time, and temperature?

What are significant figures? What is the role of uncertainty when using significant figures? Is zero a significant figure? Use examples to explain your answers.

Convert a kilosecond into milliseconds.



steps in scientific method:

Q1. List the 6 steps of the scientific method.

Q2. Define the term hypothesis and identify three ways in which a hypothesis can be tested.

Q3. Describe what happens when a hypothesis is not supported.

Q4. Describe why it is important for scientists to avoid bias.



make 2 tables one for base unite and other for derivative unte it should consist the name and symbol.

Why do physicists work in SI units?

Physicists work in SI units because it is the international system of measurement, it is consistent and easy to convert units through.

What are significant figures? What is the role of uncertainty when using significant figures? Is zero a significant figure?

Significant figures- in a measurement consist of all digits known with certainty plus one final digit which is somewhat uncertain or estimated. The role of uncertainty is just an estimate and thus cannot be more precise. A a zero is only a significant figure if it is better two none zero numbers, or if it is to the RIGHT of a decimal. Zeros in front of numbers are not significant, zeros to the left of a decimal may or may not be significant.

Convert a kilosecond into milliseconds.

One kilosecond is equivalent to 1000000 milliseconds

List the 6 steps of the scientific method.

Ask a question, form a hypothesis, experiment, observe and record, draw a conclusion, share your findings

Define the term hypothesis and identify three ways in which a hypothesis can be tested.

A hypothesis is an idea that proposes a tentative explanation about a phenomenon. Three ways a hypothesis can be tested is through: asking a question and researching, making a challenging your hypothesis, and revising it.

Describe what happens when a hypothesis is not supported.

When a hypothesis is not supported, you can go back to the drawing board and come up with a new hypothesis.

Describe why it is important for scientists to avoid bias.

It is important for scientists to avoid bias because bias can heavily affect the results of an experiment and therefore make the experiment invalid.

The correct answer is  "c".  it is "c" because melting is an endothermic change, and endothermic get's energy from surroundings.