Pure maths, physics, logic (braingames.ru): non-trade-related brain games - page 68

 
Mathemat:

P.S. One more point. A megamotive dumping snow orthogonal to the movement creates a support pressure component perpendicular to the movement (it pushes the cart orthogonal to the movement). Does this not affect the support reaction?

Ftr is proportional to the vertical component of the reaction, so throwing the snow sideways has no effect. To remove uncertainty, we can imagine that half of the snow is thrown to the right and half to the left, then these effects are fully compensated
 
TheXpert:

It does :) one side will exert more pressure and the other less. And the total friction force should increase.

But it's very short-lived. Probably can be neglected.

The farther into the woods...

It is better to neglect)))) consider the trolley and the megamotor as material points))
 

Yes, otherwise it won't be a challenge, it'll be a fucking mess. Anyway:

Можно для снятия неопределенности представить себе, что половину снега он кидает вправо, а половину - влево, тогда данные воздействия полностью компенсируются

 

And I imagine the megamotor is just a pump that continually dumps snow. So much for one-way pressure...

OK, let's not count it.

 
Mathemat:

And I imagine the megamotor is just a pump that continually shovels snow. So much for one-way pressure...

OK, let's not count it.


By the way, in the original problem condition on the site it teleported snow =), but then it was replaced by ejection for more certainty of the process
 

Problem about two bricks under the same conditions.

0 sec. a brick is placed on both trolleys // speeds change by leaps and bounds, but are the same

1 sec. the first MM throws a brick // the speed of both trolleys remains unchanged

2 sec. brick is placed on both trolleys // speeds are the same, but change by leaps and bounds The second trolley has a higher speed

materialise the third trolley with two bricks, and with the same speed as the first trolley

If the second and third bogie are not further manipulated, then the second bogie will go further than the third because it has a higher speed

3 sec. the first MM throws the brick // the speeds of the first and third carts are equal. From here on they will travel the same distance

But the second cart will go further than the third, and, consequently, the first

 
Mislaid:

Problem about two bricks under the same conditions.

0 sec. a brick is placed on both carts // the velocities change by leaps and bounds but are the same

1 sec. the first MM throws the brick // speed of both trolleys remains unchanged

What do you mean it didn't change? And the Law of Conservation of Momentum - does it not work anymore?!
 
Mathemat:

(4) There are two electric kettles with thermostats. They work like this: when the temperature drops to 70°, the heating coil turns on and a light bulb comes on; when the temperature reaches 90°, both the heating device and the light bulb turn off. On one of the kettles the light bulb comes on, on the other it does not. Which one is most likely to have hotter water and why?

The kettle with the light bulb on, because it heats up more slowly. Or you need a more specific condition.

(4) A tributary forms an acute angle as it flows into the river. On the land, inside the corner, stands the shack of Megamozg. Every day, Megamozg leaves it, goes to the tributary, meets the sunrise, then goes to the river, meets the sunset and returns to the shack. How does Megamozg need to plot a route so that the distance he walks each day is minimal? Count the banks of the river and the tributary as straight lines.

I don't know of a beautiful way of drawing it. on the principle of a ray of light -- the angle of incidence equals the angle of reflection.
 
TheXpert:


I can 't think of a beautiful way to build it. based on the principle of a ray of light -- the angle of incidence equals the angle of reflection.
I can think of an equilateral triangle. Or is it?
 
TheXpert:

In a kettle with a light bulb on, as it heats up more slowly. Or a condition needs to be more specific.


Delusional problem 100%