Prelim Physics Thread (3 Viewers)

[pikachu975]

What was your mistake pikachu975?

In my equation I wrote F = Eq and I wrote times in my post but I accidentally put divide in my calculator that's all.

 

[pikachu975]

What was your mistake pikachu975?

In my equation I wrote F = Eq and I wrote times in my post but I accidentally put divide in my calculator that's all.

 

[eyeseeyou]

A ball its thrown vertically upwards with a velocity of 100ms^-1. Calculate:
A)its time of flight
b)the maximum height reached by the ball

 

[InteGrand]

A ball its thrown vertically upwards with a velocity of 100ms^-1. Calculate:
A)its time of flight
b)the maximum height reached by the ball

 

[eyeseeyou]

Someone please help me with these 2 Q's

http://imgur.com/a/i4uSN
http://imgur.com/a/ZCEJE

Thanks again

 

[eyeseeyou]

Isn't there a more simpler way to do this (i.e. let one side be positive etc)

 

[InteGrand]

Isn't there a more simpler way to do this (i.e. let one side be positive etc)

What do you mean by letting one side be positive? The "up" direction was treated as positive, if that's what you were referring to.

 

[Fizzy_Cyst]

Isn't there a more simpler way to do this (i.e. let one side be positive etc)

You may be thinking of using Vy = Uy + ayt, solve for t when Vy=0 then double it.

But, this is essentially what integrand has done -- most students should understand both ways.

 

[eyeseeyou]

If I hurl a rock or fire an arrow or shoot using a gun, what are the forces which act on it?

 

[InteGrand]

If I hurl a rock or fire an arrow or shoot using a gun, what are the forces which act on it?

Once the projectile is in flight, the only force acting on it is gravity (ignoring things like air resistance).

 

[eyeseeyou]

Once the projectile is in flight, the only force acting on it is gravity (ignoring things like air resistance).

What about normal force and air opposing it's motion?

 

[InteGrand]

What about normal force and air opposing it's motion?

I said ignoring things like air resistance. If you don't ignore them, there's things like wind etc.

What normal force are you expecting?

 

[eyeseeyou]

I said ignoring things like air resistance. If you don't ignore them, there's things like wind etc.

What normal force are you expecting?

Like when a car is accelerating, wouldn't there be a normal force?

 

[InteGrand]

Like when a car is accelerating, wouldn't there be a normal force?

A car is resting on the ground; a ball thrown in the air isn't.

 

[eyeseeyou]

A car is resting on the ground; a ball thrown in the air isn't.

OH yeah

 

[eyeseeyou]

How would I do this question:

 

[eyeseeyou]

When it says "describe GPS" (5 marks) what should I write?

Please do not involve any scientific principles into this and the wave properties associated with as that is another thing

 

[Green Yoda]

When it says "describe GPS" (5 marks) what should I write?

Please do not involve any scientific principles into this and the wave properties associated with as that is another thing

well without scientific principle it is not physics..so GPS is Global Positioning System is basically all you can say without scientifically explaining what it is.

 

[UnbiasedProductivity]

When it says "describe GPS" (5 marks) what should I write?

Please do not involve any scientific principles into this and the wave properties associated with as that is another thing

I doubt they would simply ask "Describe GPS". It would most probably be in relation to either special relativity or the type of orbit that GPS satellites use.

 

[dragon658]

Can anyone tell me what I need to know for the HSC course, as in what carries over from Prelim?
If you could give me a thorough range of topics and important ideas that'd be great!
Thanks