Top E Planes

[Randy1]

Have you tested it?  You post with the confidence that ought to be backed by data, yet is uninformed.

How do I know?  Because I have tested it.  The Brewster does nothing unexpected.  In power on and power off tests it decelerates much, much faster than the Fw190D-9 regardless of the initial speed of the test.

Have you posted your test data?

[Karnak]

Have you posted your test data?

450-400 power on
47.56: Fw190D-9
7.56: Brewster

400-350 power on
NA.NA: Fw190D-9
11.84: Brewster

350-300 power on
NA.NA: Fw190D-9
29.53: Brewster

450-400 power off
6.69: Fw190D-9
3.51: Brewster

400-350 power off
7.44: Fw190D-9
5.18: Brewster

350-300 power off
8.38: Fw190D-9
5.62: Brewster

300-250 power off
9.47: Fw190D-9
6.87: Brewster

250-200 power off
10.41: Fw190D-9
8.31: Brewster

200-150 power off
10.43: Fw190D-9
9.50: Brewster

Fw190D-9 retains energy much better than the Brewster.

[FLOOB]

You don't know what proportional means? It's basic multiplication. It's why the Sun has more gravitational force than the Moon.

No I know what proportional means. And I said that gravitation is proportional to mass but not gravity. Scroll up.

[FLOOB]

No, it really is just because the ball filled with water had greater mass. Also, what you said about parachutes in your earlier example simply confirms that.

The speed that a parachute falls at is given by the equation SQRT(2.m.g/Rho.Cd.A) and you can clearly see that greater mass will cause it to fall faster.

Notice that in that equation if you hold gravity and drag constant, the only thing that will change the speed is the mass.

Regards

Badboy

Greater mass causes things to fall faster because inertia is proportional to mass. Thus the greater inertia the more drag required to slow an object. Not because mass changes gravity, it doesn't.

[pervert]

 

[BaldEagl]

In a vacume on Earth all objects will accelerate at 32 feet per second per second due to gravity regardless of mass, shape or size.

As soon as you add air there's a force against which the object must fall.  An object that's lighter than air won't fall at all and may actually rise.  As objects become heavier they fall faster and faster.  This has nothing to do with inertia.  The heavier object falls faster because the force of air resitance is the same against two similarily sized and shaped objects regardless of their weight so that force is less of a factor against a heavier object and more of a factor against a lighter one.

Once two objects of similar size and shape, but of differing weights are in motion at the same speed, the one with more weight has more inertia for the same reasons as stated above.  The forces acting to slow it down are less a factor than they are against the lighter object.

Weight will cause an object to accelerate quicker in air whereas inertia will keep a heavier object in motion longer than a lighter one.

[FLS]

No I know what proportional means. And I said that gravitation is proportional to mass but not gravity. Scroll up.

Gravity and gravitation refers to the same thing.

[FLOOB]

The heavier object falls faster because the force of air resitance is the same against two similarily sized and shaped objects regardless of their weight so that force is less of a factor against a heavier object and more of a factor against a lighter one.

The force is less of a factor against the heavier object why? Because a heavy object in motion requires more resistance to slow it down. That's inertia my friend.

[FLOOB]

Gravity and gravitation refers to the same thing.

When I refer to gravitation I'm refering to gravitational field, ie. your example with the moon producing weaker gravity than the earth. The force of a physical body's gravitational field is proportional to it's mass. That does not apply to what were talking about because we're not talking about how much of a gravitational field an airplane generates.

[FLS]

When I refer to gravitation I'm refering to gravitational field, ie. your example with the moon producing weaker gravity than the earth. The force of a physical body's gravitational field is proportional to it's mass. That does not apply to what were talking about because we're not talking about how much of a gravitational field an airplane generates.

So if I have a 1 lb ball and a 10 lb ball and I want to give them equal acceleration do I apply the same amount of force to both or does the 10 lb ball require more force given it's greater inertia?

[Brooke]

All of this is why the language of physics is mathematics, not prose.

The relevant equation of motion was posted a long way back by, I think, Badboy:  a = g - D/m.  You don't have to argue about terminology.  The equation says it all.

[GScholz]

So if I have a 1 lb ball and a 10 lb ball and I want to give them equal acceleration do I apply the same amount of force to both or does the 10 lb ball require more force given it's greater inertia?

That's the thing about gravity; it acts upon objects equally regardless of size or mass (unless you get into astronomical sizes). So the 1 lb ball and the 10 lb ball will both accelerate at exactly the same rate, however you would have to apply a 10 lb force to counteract the gravity of the 10 lb ball, while the 1 lb ball only requires 1 lb.

There are four forces acting upon an aircraft in a vertical climb:

Gravity: A constant 1G applies a force towards the ground that equals the weight of the aircraft.

Drag: A variable that depends on speed and the aerodynamic properties of the ariceaft.

Thrust: A variable that depends on engine power, prop efficiency and other factors.

Kinetic energy: The stored energy (inertia) of the aircraft; speed.


If the thrust is insufficient to overcome gravity and drag, the aircraft will lose kinetic energy until it is stationary and starts to fall. Gravity is constant, but drag is reduced by the square of speed. In other words when you reduce speed by half, drag is reduced to one-quarter.

The reason why kinetic energy/inertia is important is because WWII fighters have so little thrust that inertia becomes the main source of energy to overcome drag. Gravity is equal no matter the size of the aircraft so the only factors that will make a major difference between two aircraft is inertia and drag. The aircraft with the best weight to drag ratio is the better zoomer unless there is a major difference in thrust to weight ratio.

Throw a 1 lb steel ball and a 1 lb cotton ball into the air at the same speed. The steel ball will go higher due to its better aerodynamic properties; weight to drag ratio. Glue on a rubber band powered prop on both... Steel ball will still go higher.

[FLOOB]

I love you guys.

[GScholz]

I love you guys.

(Image removed from quote.)

[FLS]

That's the thing about gravity; it acts upon objects equally regardless of size or mass (unless you get into astronomical sizes). So the 1 lb ball and the 10 lb ball will both accelerate at exactly the same rate, however you would have to apply a 10 lb force to counteract the gravity of the 10 lb ball, while the 1 lb ball only requires 1 lb.

There are four forces acting upon an aircraft in a vertical climb:

Gravity: A constant 1G applies a force towards the ground that equals the weight of the aircraft.

Drag: A variable that depends on speed and the aerodynamic properties of the ariceaft.

Thrust: A variable that depends on engine power, prop efficiency and other factors.

Kinetic energy: The stored energy (inertia) of the aircraft; speed.


If the thrust is insufficient to overcome gravity and drag, the aircraft will lose kinetic energy until it is stationary and starts to fall. Gravity is constant, but drag is reduced by the square of speed. In other words when you reduce speed by half, drag is reduced to one-quarter.

The reason why kinetic energy/inertia is important is because WWII fighters have so little thrust that inertia becomes the main source of energy to overcome drag. Gravity is equal no matter the size of the aircraft so the only factors that will make a major difference between two aircraft is inertia and drag. The aircraft with the best weight to drag ratio is the better zoomer unless there is a major difference in thrust to weight ratio.

Throw a 1 lb steel ball and a 1 lb cotton ball into the air at the same speed. The steel ball will go higher due to its better aerodynamic properties; weight to drag ratio. Glue on a rubber band powered prop on both... Steel ball will still go higher.

That's quite an answer for a rhetorical question.