Question

Need help with projectile motion problems

Answer 1

Can someone explain to me how to do this problem
http://prntscr.com/79uwhd

Answer 2

You know the start point 3 feet, and you know the starting speed, so you have figure out the maximun height, using the speed and the acceleration of gravity.

After you know the maximun height, ( that is when the speed is 0 )
You now have to discover the time knowning that now you only have the acceleration of gravity.

Answer 3

Basically the equations:

Distance = initial speed * time + acceleration * time / 2

Answer 4

i'm really new to this so i don't understand fully

Answer 5

Remember that the distance you are going to find do not include the initial distance is like a differencial distance or delta space

Answer 6

Which part are you having problem with?

Answer 7

basically the whole concept

Answer 8

So, you can think of it as a rocket, the greater the initial speed the higher he will go, but he is going to slow down and stop , because of gravity, so you what we want to know is how high he is going to stop

Answer 9

so we need to find the highest point before it starts to go down?

Answer 10

Exaclty

Answer 11

And there is an equation for that

Answer 12

ok what next

Answer 13

So there is a reason for him to start going down

Answer 14

It is because he doesn't have any more speed, so he doesn't move up anymore, it means that all the acceleration that goes against him worked "like a car brake"

The equation we use for that is Final Speed = Initial Speed + Acceleration* Time

Answer 15

We now the initial speed ( velocity = 13feet per second), and the final speed we want is 0, and the acceleration of gravity in feet is approximated to 32 feet per second, so we have everything but the time, and that is what we want to find, so could you find the time for me?