First example: book, m= 0.75 kg, h=1.5 m, g= 9.8 m/s², it has only potential energy Ep,
Ep=m*g*h=0.75*9.8*1.5=11.025 J
Second example: brick, m=2.5 kg, v=10 m/s, h=4 m, it has potential energy Ep and kinetic energy Ek,
E=Ep+Ek=m*g*h + (1/2)*m*v²=98 J + 125 J= 223 J
Third example: ball, m=0.25 kg, v= 10 m/s, it has only kinetic energy Ek
Ek=(1/2)*m*v²=12.5 J.
Fourth example: stone, m=0.7 kg, h=7 m, it has only potential energy Ep,
Ep=m*g*h=0.7*9.8*7=48.02 J
The order of examples starting with the lowest energy:
1. book, 2. ball, 3. stone, 4. brick
Slicing a tomato is still considered a physical change because you are only altering the shape of it by slicing it. It does not change color or make bubble when slicing the tomato. Therefore, it is still a physical change
hope this helps:)
Answer:
1.29649
488.08706 nm

231715700.28346 m/s
Explanation:
n denotes refractive index
1 denotes air
2 denotes solution
= 632.8 nm
From Snell's law we have the relation

Refractive index of the solution is 1.29649
Wavelength is given by

The wavelength of the solution is 488.08706 nm
Frequency is given by

The frequency is 

The speed in the solution is 231715700.28346 m/s
They are the physics of the world??
In 2.34 hours, the bus travels 16.34 km.
Average speed = (distance covered) / (time to cover the distance).
Average speed = (16.34 km) / (2.34 hours) = 6.983 km/hr