Title Colombian Olympiad Physics 2.2 MB 120
##### Document Text Contents
Page 1

Training Problems

Problem 1-1

A hinge construction comprises three diamonds whose side lengths are in the proportions 3:2:1. Vertex A 3 is
shifted in the horizontal direction with velocity V constant. Determine the velocities of the
vertices A 1, A 2, B 2 at all angles of the building are straight.

Problem 1-2

In a movie screen shows the movement of a car. The radius of the front wheels of the car is r = 0.35 m and the
rear R of r = 1.5. The front wheels have N 1 = 6 radios. The camera filming the film moves at a speed of 24
frames per second.

a) Considering that the wheels of the car move without slipping, determine the minimum speed at which the
car must be moved to the front wheels appear to rotate in the screen.

b) What is the minimum number of radios N 2 which must be to the rear wheels while the front also appear to
not rotate?

For the next question considering that the number of spokes of the front and rear wheels is N 1 = N 2 = 6.

c) How fast is the car moving from left to right, to a spectator will appear that the spokes of the wheels rotate
in a counter clockwise?

Problem 1-3

Two tanks are moving on a horizontal ground so that approximate along the same line with constant speed as
shown. Each tank fires a shot at the same time in the same vertical plane of the other tank. The speed of each
projectile with respect to the tank is u 1 and u 2 and the respective angles with the horizontal 1 2. Both
shot tanks impinging upon.

a) Find the relative speed of the tanks.

b) Find the condition required for u 1, u 2 and 1, 2. Neglecting air resistance constant and assume the value of
the acceleration of gravity). What if the above condition is not satisfied?

Page 60

 0 is the angle between the incident beam to the limit "lens-air."

From the expressions obtained for small values  0,   when

sin    obtain:

Because , Then .

Analyzing the course of a beam of rays parallel to the optical axis moving

Main can demonstrate the same way that

,

therefore:

, (2)

From equations (1) and (2) we obtain

that was what we wanted to demonstrate

REVIEW of 1 Secondary

SOLUTIONS

1. If a measured person 1782 m , How many miles it measured?

a) 1782 Km b) 1782 Km c) MKM 1782 d) 0.0001782 Km e)

___

Solution

Prefix used:

 Do not forget the prefixes:

TAB

LE 1.1
Number Decimal Power Prefix Symbol

10000000000000000000000000

Yotta And

1000000000000000000000

Zetta Z

Page 119

If a change occurs very slowly so that at each moment the system is in an equilibrium position

then the process is reversible. And if the system away from its equilibrium state then the
process is irreversible.
When there is a change in system pressure or volume but the temperature is kept constant is

spoken of an isothermal process.
When there are non-heat exchange between the system and the environment comes to an

8) Explain what the Doppler effect.
When a person hears a sound is moving toward the stationary source that produces it, the

frequency of the sound heard is greater than when at rest. If the person is moving away from

the stationary source, less frequently heard when this than when at rest. Similarly is the

equivalent when both source and person move away from or towards. This effect applies to all
waves in general.

Practical part
5) A disc of 0.5 [m] radius and 20 [kg] of mass can rotate freely about a fixed horizontal axis

passing through its center. Applies a force F of 9.8 [N] pulling a cord coiled around the edge of

the disc.Find the angular acceleration of the disk and its angular velocity after 2 [s]. Finding the
reaction force also exists in the brackets which support the axis of the disc.
Sun -

6) A semiquantitative definition of electric flux is: . And Gauss's law tells

us that: q . Write the electric field of a point charge q taking Gaussian surface as a

sphere of radius r. Help: The total area of a sphere is r 2 and the

vectors and have the same direction.

7) A boat in motion produces surface waves on a calm lake. The boat runs 12 oscillations in 20

[s]; each oscillation produces a wave crest. The crest of the wave takes 6 [s] to reach the distant

shore 12 [m]. Calculate the wavelength of surface waves.

8) Three capacitors of 1.5  F], 2  F] and 3  F] are connected in a) series, b) are parallel

and applies a potential difference of 20 [V]. Determine in each case i) the capacitance of the
system, ii) loading and the potential difference of each capacitor, iii) energy of the system.