Equations of Motion (Deriving equations)

AI Thread Summary
To derive the equation for velocity as a function of acceleration and time, start with the definition of acceleration as the change in velocity over time, a(t) = dv(t)/dt. Integrate both sides from the initial time t0 to time t, resulting in v(t) - v0 = ∫a(t) dt. This integral provides a relationship between velocity and acceleration, but it needs to be expressed as v = f(a, t). To achieve this, an assumption about the nature of acceleration is necessary, which can transform the integral into a function of acceleration and time. The final equation is v = v0 + a(t2 - t1).
arjun90
Messages
4
Reaction score
0
Hi, I am just wondering how you would approach this problem:
Using the definitions below, derive an equation for velocity as a function of acceleration and time (v=f(a,t)). Assume initial velocity is Vo. The answer to this problem is v=v0+a(t2-t1). My question is how would you arrive to this answer step-by-step. Below are the definitions:

x=current position in the x dimension
deltax= change in position
t=time now, t0 is the starting time.
deltat= a time interval, t2-t1.
v=deltax/deltat (use as a scaler for now).
deltav= a change in velocity.
a=deltav/deltat (Use as a scaler for now).

Subscripts: 0 is an initial value, other numbers are subsequent values in time order as needed.

v (average)= (v1+v2)/2, a simple average.

Any help will be appreciated. Thank you.
 
Physics news on Phys.org
# I would first look at the definitaion of a
a(t) = \frac{dv(t)}{dt}
# Integrate both sides
\int^{t}_{t_0} a(t) dt = v(t) - v(0)
# This is the relation between v and a. but it is not in the form of you want, i.e. v=f(a,t). It is an integral equation.
# So, there should be an assumption about a, which changes integral the relation between a and v to a function. I think if you think, you can find it by yourself.
 
Last edited:
I multiplied the values first without the error limit. Got 19.38. rounded it off to 2 significant figures since the given data has 2 significant figures. So = 19. For error I used the above formula. It comes out about 1.48. Now my question is. Should I write the answer as 19±1.5 (rounding 1.48 to 2 significant figures) OR should I write it as 19±1. So in short, should the error have same number of significant figures as the mean value or should it have the same number of decimal places as...
Thread 'A cylinder connected to a hanging mass'
Let's declare that for the cylinder, mass = M = 10 kg Radius = R = 4 m For the wall and the floor, Friction coeff = ##\mu## = 0.5 For the hanging mass, mass = m = 11 kg First, we divide the force according to their respective plane (x and y thing, correct me if I'm wrong) and according to which, cylinder or the hanging mass, they're working on. Force on the hanging mass $$mg - T = ma$$ Force(Cylinder) on y $$N_f + f_w - Mg = 0$$ Force(Cylinder) on x $$T + f_f - N_w = Ma$$ There's also...
Back
Top