Ox:vₓ=v₀
x=v₀t
Oy:y=h-gt²/2
|vy|=gt
tgα=|vy|/vₓ=gt/v₀=>t=v₀tgα/g
y=0=>h=gt²/2=v₀²tg²α/2g=>tgα=√(2gh/v₀²)=√(2*10*20/24²)=√(400/576)=0.83=>α=tg⁻¹0.83=39°
cosα=vₓ/v=v₀/v=>v=v₀/cosα=24/cos39°=24/0,77=31.16 m/s
Ec=mv²/2=2*31.16²/2=971.47 J=>Ec≈0.97 kJ
When acceleration is constant, the average velocity is given by
where 
and 
are the final and initial velocities, respectively. By definition, we also have that the average velocity is given by
where 
are the final/initial displacements, and 
are the final/initial times, respectively.
Take the car's starting position to be at 
. Then
So we have
You also could have first found the acceleration using the equation
then solve for 
via
but that would have involved a bit more work, and it turns out we didn't need to know the precise value of 
anyway.
Hard surfaces reflect sound back into the room, while carpets help to absorb the sound so it reflects less
Hi! In 3 seconds the object will fall approximately 44 meters.
