CN2209371Y - Force analysis demonstrator for body on slope - Google Patents

Abstract

The utility model relates to a force analysis demonstrator for objects on a slope, which is composed of a bottom plate, a panel, an indicating needle, a slope member and a horizontal member. The bottom plate 1 is drawn with two circumscribed circles 7, 8 with the diameter which is equal to the length of the indicating needle 3. The panel 2 is provided with a cruciform passing through the center point of the panel. The slope member 4 whose one end is hinged with one end of the horizontal member 5 is fixed on the edge of the bottom margin of the panel. The bottom plate, the panel and the indicating needle are connected by a shaft pin 10. The bottom plate is provided with a circular arc positioning slideway (11). The horizontal member is fixed on the circular arc positioning slideway through a turn button 6. The utility model has the advantages of simple structure and reasonable structure, and can visually and continuously carry out correct force analysis to the object on the slope.

Description

Force analysis demonstrator for body on slope

The utility model relates to object receiving force analytical demonstrator on a kind of inclined-plane, belongs to teaching aid.

Be still in that the force analysis of object is important content in the physics lesson of middle school on the inclined-plane, the teacher is when giving lessons, normally adopt graphic analytic method, on blackboard, draw the object receiving force analysis chart, analyze from the mathematics angle, this method is promptly lost time, can not allow the student recognize variation intuitively again along with inclination angle of inclined plane θ, the power F1=mgsin θ that object gravity mg glides along the inclined-plane and compress the power F2=mgcos θ on inclined-plane and inclined-plane to variation tendency and the size of the holding power N and the stiction F of object perpendicular to the inclined-plane promptly adopts graphic method to lack continuity and intuitive.

The purpose of this utility model is to provide a kind of variation tendency that can reflect above-mentioned each power with the inclined-plane tiltangle continuously, and can embody object receiving force analytical demonstrator on the inclined-plane of size and Orientation of each power intuitively, to overcome above-mentioned deficiency.

The object receiving force analytical demonstrator is made up of base plate, panel, pointer, ramp member and horizontal member on the inclined-plane that the utility model proposes.Draw the circumcircle that two diameters equal pointer length (distance that pointer round dot to pointer is not held) on base plate, the straight line at place, the two circumcircle centers of circle is perpendicular to the base plate base.Offer two mutually perpendicular cruciform strias on panel, wherein stria is parallel to the base of panel.Ramp member is fixed on the edge, base of panel, an end hinge of an end of ramp member and horizontal member.Above-mentioned pointer, panel, base plate pass two circumscribed point of contacts on the intersection point of cruciform stria on the round dot, panel of pointer and the base successively by pivot pin, and pointer, panel, base plate are linked together.Panel can rotate around pivot pin, the fixing and vertical base of pointing to base plate of the relative base plate of pointer.Simultaneously, above-mentioned base plate is the center of circle with the point that the length at distance point of contact equals horizontal member length on above-mentioned two circumscribed common tangents, with the distance at center to the point of contact of horizontal member and ramp member hinge is to offer one section circular arc limit sliding chutes on the circle of radius.The other end of above-mentioned horizontal member is fixed on the base plate by the knob on the above-mentioned circular arc limit sliding chutes, and can slide along the circular arc limit sliding chutes.Can make panel and ramp member rotate and control the size of inclination angle of inclined plane θ flexibly around pivot pin by knob on the circular arc stopper slot.

The object receiving force analytical demonstrator utilizes the continuous action relation of pivot pin, panel, ramp member, horizontal member and circular arc limit sliding chutes on the utility model inclined-plane, reflect when inclination angle of inclined plane θ changes object gravity, the decomposition of gravity and the variation relation of holding power and friction force on the inclined-plane intuitively, continuously, and can embody each power size and Orientation exactly.The object receiving force analytical demonstrator has advantages such as simple and reasonable for structure on the inclined-plane simultaneously.

Below in conjunction with drawings and Examples the utility model is further described.

Accompanying drawing is the structural representation of object receiving force analytical demonstrator on the inclined-plane.

With reference to accompanying drawing, the object receiving force analytical demonstrator is made up of base plate 1, panel 2, pointer 3, ramp member 4 and horizontal member 5 on the inclined-plane.On base plate 1, be decorated with the line in circumcircle 7,8, two circumcircles 7,8 centers of circle that two diameters equal pointer 3 length (distance that pointer 3 round dots are not held to pointer 3) perpendicular to the base of base plate 1, two circumcircles 7,8 outside, draw an envelope simultaneously and justify 9.Ramp member 4 is fixed on the positive lower limb of panel 2, and with horizontal member 5 at left end place hinge.On the panel 2 by the central point of panel 2 about and respectively offer one up and down and be parallel to ramp member 4 and a stria perpendicular to ramp member 4, stria should not be too wide.Length upper and lower and left stria equals pointer length, and the length of right stria equals 0.7 times of pointer length.Pointer 3, panel 2, base plate 1 pass two circumcircles 7,8 on the central point of round dot, panel 2 of pointer 3 and the base 1 successively by pivot pin 10 point of contact links together.Panel 2 may rotate by pivot pin 10, pointer 3 relative the base plates 1 fixing and vertical base of pointing to base plate 1.Under the position, right-hand member place of horizontal member 5, on base plate 1, offer a circular arc limit sliding chutes 11.This circular arc limit sliding chutes 11 is to determine like this, the point that equals horizontal member 5 length with the distance at the common tangent rightmargin point of contact of two circumcircles 7,8 is the center of circle, is one section circular arc of radius with the distance at two stria point of crossing to the hinge center of ramp member 4 and horizontal member 5.The right-hand member of the equal part 5 of level is fixed on the base plate 1 by the knob on the circular arc limit sliding chutes 11 6, and can slide along circular arc limit sliding chutes 11.By the knob on the circular arc stopper slot 11 6 panel 2 and ramp member 4 are rotated flexibly around pivot pin 10, and the size of control inclination angle of inclined plane θ.In order to increase intuitive and appreciation effect, base plate 1, panel 2 and envelope are justified 9, go up the circle of contact 7, are descended the circle of contact 8 and pointer 3 etc. can be applied to different colors, and on two circumcircles 7,8 and pointer 3, draw equidistant camber line, and at base plate 1 and panel 2 subscript upper angle scales, so that the angle of inclination angle of inclined plane θ and pointer 3 is shown.

Claims (1)

1, object receiving force analytical demonstrator on a kind of inclined-plane, it is characterized in that: by base plate (1), panel (2), pointer (3), ramp member (4) and horizontal member (5) are formed, go up the circumcircle (7) that two diameters of picture equal pointer (3) length at base plate (1), (8), two circumcircles (7), (8) straight line at place, the center of circle is perpendicular to base plate (1) base, on panel (2), offer two mutually perpendicular cruciform strias, wherein stria is parallel to the base of panel (2), ramp member (4) is fixed on the edge, base of panel (2), one end hinge of one end of ramp member (4) and horizontal member (5), pointer (3), panel (2), base plate (1) passes the round dot of pointer (3) successively by pivot pin (11), panel (2) is gone up the intersection point and base (3) last two circumcircles (7) of cruciform stria, (8) point of contact, and with pointer (3), panel (2), base plate (1) links together, panel (2) can rotate around pivot pin (11), pointer (3) is the fixing and vertical base of pointing to base plate (1) of base plate (1) relatively, simultaneously, base plate (1) is in two circumcircles (7), (8) point that equals horizontal member (5) length with the length at distance point of contact on the common tangent is the center of circle, be to offer one section circular arc limit sliding chutes (11) on the circle of radius with the distance at center to the point of contact of horizontal member (5) and ramp member (4) hinge, the other end of horizontal member (5) is fixed on the base plate (1) by the knob (6) on the circular arc limit sliding chutes (11).

Images