Work formula P = w / t time formula w = P * t power formula t = w / P

Work formula P = w / t time formula w = P * t power formula t = w / P

P is electric power, W is electric power, t is time
The formula P = w / T represents the amount of work done per unit time, so electric power is expressed by dividing electric work by time
The formulas w = P * t and T = w / P are derived mathematically from the above formula

Is the W of physical power P = w / T active work or total work
If a moving pulley is used to lift an object, and two strands of rope bear gravity, is the effective work done by the pulling force on the object equal to the pulling force × the distance of the hand moving, or is the total work done by the pulling force × the distance of the hand moving × the number of ropes

P=W/t
All work is used without distinction
Of course, if the useful work W is divided by the corresponding time, P is the power of the useful work. Similarly, if the total work W is divided by the corresponding time, P is the power of the total work
For the moving pulley lifting object, the total work is equal to the pulling force x the moving distance of the free end of the rope, w = FS
The active work is equal to the gravity of the weight × the lifting height of the weight W = GH

The analytical formula of V (T) of the vehicle starting at constant power (known power P, constant resistance F, vehicle mass m) is obtained by 10 points

If the traction force of the vehicle at starting is f, it can be known from the formula P = f * V:
F = P / V is expressed by Newton's second law
Acceleration a = (f-f) / M = (P / V-F) / M and a = V / T
So V / T = (P / V-F) / M equation is deformed, and both sides are multiplied by VTM
MV ^ 2 + FVT Pt = 0 can be solved by the spherical root formula of quadratic equation
V1=[-ft+(f^2*t^2+4mpt)^1/2]/2m V2=[-ft-(f^2*t^2+4mpt)^1/2]/2m
Because all physical quantities are positive, V2 is discarded
So V (T) = [- FT + (f ^ 2 * T ^ 2 + 4mpt) ^ 1 / 2] / 2m