In college physics, dr/dt=? (r is thin, but there is no direction. What is the meaning of dr/dt? R is a vector form, how can there be no direction! Dr/dt is the vector speed, with magnitude and direction, and magnitude indicates the speed of motion!
Who is the first derivative of dr/dt in college physics? If the R in dr/dt is not bold, it means that R is only the module of position vector. At this time, the derivation is that the modulus of the position vector is derived from time to get the velocity.
What is the meaning of dr/dt in particle motion in college physics? Dr/dt refers to the radius change rate or the amplitude change of radius per unit time.
basic content
First, the basic requirements:
(1) Grasp the physical quantities describing the motion state and state change of particles and their significance.
(2)? Master the calculation of two kinds of kinematic problems.
(3) Understand the concepts of tangential acceleration and normal acceleration.
(4) Understand the relative motion.
Second, the basic content
Basic physical quantities describing particle kinematics.
(1) position vector
(2) Displacement
(3) Speed
(4) acceleration
Kneel to find the difference between the absolute values of dv vector /dt dv/dt dr/dt dr vector /dt dv vector /dt in college physics. Thank you. Dv vector /dt: represents the acceleration vector;
Dv/dt: it is the rate that changes with time (that is, a scalar);
Dr/dt: the rate of change of the modulus (and the magnitude of R) of the position vector with time;
Dr vector /dt: velocity vector;
The absolute value of dv vector /dt: the magnitude of acceleration.
Why can we split d/dt(r×mv)=r×d(mv)/dt dr/dt ×mv in physics? The vector in physics is regarded as an unknown number in mathematics. f(x)g(x) is equal to the derivative of f(x) multiplied by g(x) plus the derivative of f(x) multiplied by g(x), the above formula and this. That's understandable.
Dr/dt in college physics is not equal to v, but ds/dt = v? The latter can be understood. How should dr (non-vector) in the former be understood? Radial rate?
College physics, angular acceleration of rigid body, β = dw/dt = d 2× α/dt 2, what does d stand for? Angular acceleration is equal to the second derivative of angular displacement with respect to time.
Is angular velocity scalar or vector in college physics? Angular velocity is a vector in college physics. Direction angular velocity direction: perpendicular to the plane of rotation.