Physics Simplified

PHYSICS

Calculation of Distance.

Question:

A car travels with a speed of 30 m/s for 20 s. Calculate the distance covered at the end of the motion.

Solution

Speed = 30 m/s
Time = 20 s
Distance = Speed × Time
= 30 × 20
= 600 m

Physics become much easier when students know which formulae to us, what each symbol represents and the current unit.
I have put together this physics formulae sheet covering.
1. General Physics.
2. Thermal Physics.
3. Waves.
4. Electricity & Magnetism.
5. Space Physics.
6. Important graph relationship and equation.

Best use for: Quick revision before exams Formula recall Solving numerical problems Last minute preparations Classroom preparation

Save it. Revise it. Practice it. Master it

SPEED — CALCULATION

Formula

Speed = Distance / Time

Or Simply

S = D/T

2. What does it mean?

S = Speed
D = Distance travelled
T = Time taken

👉 Speed tells us how fast an object is moving.

3. Unit of speed

The SI unit of speed is:

metre per second (m/s)

This means how many metres an object travels in one second.

Examples on the board..

Blue sky.

Yes the sky is blue, is a popular sentence we hear everyday but have you pause ask, is the sky truly blue and why.

Rayleigh scattering is a phenomenon that explains why the sky is blue.

Here's the simple explanation:
Sunlight looks white, but it is actually made up of many colors—red, orange, yellow, green, blue, indigo, and violet.

When sunlight enters Earth's atmosphere, it encounters tiny molecules of gases such as nitrogen and oxygen.

These molecules scatter the sunlight in different directions.

The important part is that shorter wavelengths of light scatter much more strongly than longer wavelengths.
🔴 Red → longer wavelength → scatters less
🟠 Orange → scatters less
🟡 Yellow → scatters more than red
🔵 Blue → short wavelength → scatters strongly
🟣 Violet → even shorter wavelength → scatters very strongly

So why don't we see a violet sky instead?
Because our eyes are more sensitive to blue than violet, and some of the incoming violet light is absorbed higher in the atmosphere.
The combined effect makes the sky appear predominantly blue.

But standing on the moon, the sky would look black even during the day because the moon has almost no atmosphere to scatter sunlight like the earth atmosphere does..

Picture A is the sky from the earth.
Picture B is the sky from the Moon.

How I Introduce Speed to My Students in 45 minutes.,

I Start by reminding them about yesterday.

Teacher: Yesterday, what did we learn about distance?

Students: Distance = How Far

Teacher: If I walk from this classroom to the school gate, what am I measuring?

Students: Distance.

Teacher: Good! So distance tells us “ How Far “ something has travelled.

I Wrote on the board

DISTANCE = HOW FAR?

Teacher: Imagine two students, Emeka and Chinedu, are asked to walk from the classroom to the school gate.

The distance from the classroom to the gate is 100 metres.

Emeka gets to the gate in 20 seconds.

Chinedu gets there in 50 seconds.

Teacher: Who is faster?

Students: Emeka!

Teacher: But wait... did they travel the same distance?

Students: Yes!

Teacher: Then why did Emeka get there first?

Teacher: Because Emeka covered the same distance in less time.

And that is where speed comes in.
This introduced the lesson for the Day “SPEED”

Teacher: What is speed?

Speed tells us how quickly an object covers a distance.

Or

Speed tells us how fast something is moving.

Teacher: SPEED = HOW FAST?

Students: Distance → How far?
Speed → How fast?

Teacher: Now let me use an everyday example.
When you are going to school, who gets to school faster: someone who walks or someone who rides a motorcycle, assuming they start from the same place?

Students: Motorcycle!

Teacher: Why?

Students: Because the motorcycle is faster.

Teacher: Exactly!
The motorcycle covers a particular distance in a shorter time. That is why we say it has a greater speed.

Teachers: If speed tells us how much distance is covered in a certain amount of time, how can we calculate it?

Speed = Distance ÷ Time

This is how I teach physics by drawing their attention to their everyday experience..

It was during our astronomy class in 300L that our lecturer, classified Pluto as a dwarf planet.

It doesn’t meet the requirements of being a planet .

A planet must be big enough to dominate its orbital neighborhood.

Pluto is round and orbits the Sun, but it doesn't dominate its neighborhood, so it is a dwarf planet.

Even though Pluto orbits the sun, its orbit lies within the region called the KUIPER BELT.

The Kuiper Belt is a large region of our Solar System beyond the orbit of Neptune.

Beyond the Neptune is the Kuiper Belt, that’s where the Pluto is, beyond Pluto is the farther space.

Sun → planets → Neptune → Kuiper Belt → farther space

It’s not only Pluto that can be found kuiper Pluto ( he get neighbors 😀) but it’s the largest of them all, that’s why it was initially spotted and classified as a planet.

Astronomy swt shaa, one of my favorite courses, it makes one to start feeling like a voltron.

DISTANCE = HOW FAR

Yesterday I was teaching my students about distance..
It was interactive and goes like this

Teacher: If I move from this classroom to the school gate, what am I doing?

Students: You are moving!

Teacher: Good! Now, what can we measure about my movement?

Students: How fa you moved.

Teacher: Exactly! That “ How far “ is called distance.

Distance is simply the length of path travelled by an object.
For example if I walk 20meters from the classroom to the gate.
Distance travelled = 20m

Distance = How far

Ready to ace your Physics exams without stress? Join the Physics Masterclass designed specifically for SS1, SS2, and SS3 students preparing for WAEC, JAMB, and NECO!