Find the acceleration, velocity and position

AI Thread Summary
The discussion focuses on calculating the acceleration, velocity, and position of a sprinter with a mass of 80 kg, subjected to a constant horizontal force of 400 N and air resistance. The initial acceleration is determined as a1 = 400 N / 80 kg. The air resistance formula is provided, and participants discuss the need for numerical methods to solve for velocity and position due to the complexity of the equations involved. Suggestions include using initial acceleration conditions and differential equations to derive a logarithmic function of velocity over time. The conversation emphasizes the importance of numerical solutions and the application of learned methods from coursework.
MaxManus
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Homework Statement


The motion of a sprinter with
mass = 80 Kg
the sprinter is accelerated with a constant horizontal force: 400 N
The air resistance is 0.5*p*Cd*A*(v-w)**2
p = 1.293 kg/m**3
Cd = 1.2
A = 0.45 m**2
v = velocity
w = 0 m/s

find the acceleration, velocity and position

The Attempt at a Solution


a1 = 400N/80kg

a(t) = a1*t - (1/m)*0.5*p*Cd*A*(v)**2

Can someone help me with the v?
I am allowed to solve it numerically
 
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MaxManus said:

Homework Statement


The motion of a sprinter with
mass = 80 Kg
the sprinter is accelerated with a constant horizontal force: 400 N
The air resistance is 0.5*p*Cd*A*(v-w)**2
p = 1.293 kg/m**3
Cd = 1.2
A = 0.45 m**2
v = velocity
w = 0 m/s

find the acceleration, velocity and position

The Attempt at a Solution


a1 = 400N/80kg

a(t) = a1*t - (1/m)*0.5*p*Cd*A*(v)**2

What is the a1*t term supposed to represent?

Can someone help me with the v?
I am allowed to solve it numerically
I think this one can only be solved numerically. What have you been taught so far about that? There are many different ways to solve it numerically, it would be good if you can tell us what your professor or textbook says about this.
 
Solved, I will post my solution later.
 
Use initial acceleration condition and differential equations to solve the problem you geta logarithimic function of velocity with time..now again use same to get position as a function of time .
 
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