Alterna · учебный материал
Movement of body at an angle
Without air resistance, the horizontal projection of speed is constant, and the vertical change under g. The combination of the two movements gives parabola.
Что в этом материале
- The physical picture
- Laws and values
- Links and application
- What needs to be understood
- Terms of the topic
- Origin and conclusion of the formulas
- Model boundaries and typical errors
- Conclusion on the topic
Содержание и основные понятия
Without air resistance, the horizontal projection of speed is constant, and the vertical change under g. The combination of the two movements gives parabola.
GEF · 10 grade
PIF · Baseline
Interactive model
Parabola
range
altitude
independence of movements
01
The physical picture
What happens and what boundaries the model has.
Main message
Without air resistance, the horizontal projection of speed is constant, and the vertical change under g. The combination of the two movements gives parabola.
The flight time is determined by the vertical component of the initial speed.
The range at one level is maximum at 45° coal.
At the top, the vertical velocity is zero, horizontal is maintained.
How to reason
First, name the system and the interaction, then select the values, and only then write down the law. The formula works within the model's assumptions.
02
Laws and values
Symbols should be read as a relationship of values, not as a recipe for substitution.
x
=
v
0
cos
α
t
x=v_0\cos\alpha\,t
x
=
v
0
cos
α
t
horizontal coordinate
y
=
v
0
sin
α
t
−
g
t
2
2
y=v_0\sin\alpha\,t-\frac{gt^2}{2}
y
=
v
0
sin
α
t
−
2
g
t
2
vertical coordinate
Review of the situation
Two bodies, one released, the other dumped horizontally from the same height, fall simultaneously in the absence of air.
04
Links and application
In the real world
Two bodies, one released, the other dumped horizontally from the same height, fall simultaneously in the absence of air.
Model verification
Compare the prediction with observation, evaluate the units, the order of magnitude and the influence of the factors not taken into account. Disparity does not always mean an error of law: often idealization is no longer sufficient.
C
What needs to be understood
Outcome 1
To explain the physical meaning of the topic "The movement of an angled body" through the model, not just through the formula.
Outcome 2
Clear and correct use of terms: parabola, range, altitude.
Outcome 3
Indicate the conditions for the applicability of the law, verify units and limit cases.
T
Terms of the topic
The definition should indicate the physical meaning, not a substitute for a domestic synonym.
Parabola
The second-order curve; in a homogeneous field without resistance, is the trajectory of an angled body.
range
Horizontal distance from the point of discharge to the point at which the selected traffic model enters.
altitude
Vertical coordinate or vertical distance relative to the selected level.
independence of movements
The principle of the decomposition of traffic on mutually perpendicular axles, each of which is analysed separately.
F
Origin and conclusion of the formulas
The fundamental law cannot be "proven" by algebras: for each record, it is stated whether it is a definition, an experimental law, or a model effect.
x
=
v
0
cos
α
t
x=v_0\cos\alpha\,t
x
=
v
0
cos
α
t
model effect
Horizontal coordinate.
The following is an indication of the definition, experience or law from which this entry arises and where it is applicable.
v
0
x
=
v
0
cos
α
v_{0x}=v_0\cos\alpha
v
0
x
=
v
0
cos
α
The initial speed shall be placed on both horizontal and vertical components.
a
x
=
0
⇒
v
x
=
v
0
x
a_x=0\quad\Rightarrow\quad v_x=v_{0x}
a
x
=
0
⇒
v
x
=
v
0
x
There is no horizontal force in the model without air resistance, so the horizontal velocity is constant.
x
−
x
0
=
v
x
t
x-x_0=v_xt
x
−
x
0
=
v
x
t
At x0 = 0, the uniform motion law gives the formula.
Conditions:
Uniform field of gravity, air resistance neglected, axis x horizontal, x0 = 0, time shall be taken from the throw.
Monitoring:
The dimensions of both parts shall coincide; the result shall be checked for sign, order and limit case.
y
=
v
0
sin
α
t
−
g
t
2
2
y=v_0\sin\alpha\,t-\frac{gt^2}{2}
y
=
v
0
sin
α
t
−
2
g
t
2
model effect
Vertical coordinate.
The following is an indication of the definition, experience or law from which this entry arises and where it is applicable.
v
0
y
=
v
0
sin
α
v_{0y}=v_0\sin\alpha
v
0
y
=
v
0
sin
α
The vertical component of the initial speed is obtained by a projection on the y-axis.
a
y
=
−
g
a_y=-g
a
y
=
−
g
In the upward direction of the axle, the acceleration of the free fall shall be negative projection.
y
−
y
0
=
v
0
y
t
+
a
y
t
2
2
y-y_0=v_{0y}t+\frac{a_yt^2}{2}
y
−
y
0
=
v
0
y
t
+
2
a
y
t
2
The Y0 setup = 0 and a ± = -g to the law of equal acceleration gives the formula.
Conditions:
Uniform field of gravity with constant g, air resistance neglected, axis y directed upwards, y0 = 0.
Monitoring:
The dimensions of both parts shall coincide; the result shall be checked for sign, order and limit case.
!
Model boundaries and typical errors
Error: Forget model condition
You can't move the formula to any situation just because the letters match. The key condition of this subject is that time of flight is determined by the vertical component of the initial speed.
How to Check the Mind
The distance at one level is maximum at 45°. Then check the units, vector direction, and result behaviour at zero or very large parameter.
Σ
Conclusion on the topic
Movement of body at an angle
Without air resistance, the horizontal projection of speed is constant, and the vertical change under g. The combination of the two movements gives parabola.
The flight time is determined by the vertical component of the initial speed.
The range at one level is maximum at 45° coal.
Any numerical result shall be accompanied by a unit, a sign and an explanation of its physical meaning.
The content is consistent with the FRP on Physics of the OS/OSS 2025 and the subject matter of the current lines of the PNP: I. M. Peryškin and co-authors (7–9), G. J. Mäkishev and coauthors (10–11), and with the lines "Engineers of the Future" and V. A. Kasyanov. The original texts are not reproduced, the text of the textbooks is not reproduced.