Projectile motion question (1 Viewer)

[Nailgun]

Having issues with a question from the Jacaranda textbook, the answer given is 115,000m and I (eventually) got 114,665.56m (Jacaranda tends to round things randomly?) but still not sure if I'm doing it correctly.

Q. A coastal defence cannon fires a shell at 45 degrees from the top of a 50.0 m high cliff, directed out to sea with a velocity of 1060.0 m s^−1. What is the range?

Much appreciated

 

[Silly Sausage]

Check your sig figs rules, since your answer should have as many sig figs as the value given with the LEAST amount of sig figs. (50.0m) Hence, the answer is 115000 (3 sig figs).

 

[Nailgun]

Oh okay, that makes the other answers make a lot more sense.
Just to be sure with the method, you have to use the quadratic formula right?

 

[Silly Sausage]

Oh okay, that makes the other answers make a lot more sense.
Just to be sure with the method, you have to use the quadratic formula right?

Depends on which formula you use. If you use then you wont have to. Don't remember if this is the HSC or not.

 

[Drsoccerball]

Depends on which formula you use. If you use then you wont have to. Don't remember if this is the HSC or not.

Nop you can't just pop that formula out of no where. Also it's ex 1 and thus we arn't expected to derive it in physics.

 

[Nailgun]

erm, never seen that formula before so I'm guessing no?
Since it's parabolic I guess it makes sense to use the quadratic formula, but yeah.
Thanks for the help, much appreciated

 

[InteGrand]

 

[Nailgun]

Yeah, that's how I thought it would be done. Thanks for the help