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The Motion Of A Particle Is Defined By A Relation V=4t^2 - 3t - 1 Where V Is In M/s And T Is In Sec

The acceleration of a particle is defined by the relation a=kt^2.?

a = k*t^2

v = int(a dt)

v =1/3*k*t^3 + C1

when t = 0, v = v0.
v0 = C1

therefore:
v = 1/3*k*t^3 + v0

when t=t1, v=v1:
v1 = 1/3*k*t1^3 + v0

solve for k:
k = 3*(v1-v0)/t1^3

Re-construct our velocity equation:
v = (v1-v0)*(t/t1)^3 + v0

integrate to find x:
x = int(v, t)

x = 1/4*(v1-v0)*t^4/t1^3+v0*t + C2

using x=0 at t = t1:
0 = 1/4*(v1-v0)*t1^4/t1^3+v0*t1 + C2

Solve for C2:
C2 = -1/4*t1*v1-3/4*v0*t1

Re-construct x:
x = 1/4*(v1-v0)*t^4/t1^3+v0*t -1/4*t1*v1 - 3/4*v0*t1

Data:
v0:=-32 ft/s; v1:=32 ft/s; t1:=4 s;

Results:
(A) k = 3 ft/s^4
(B) Here are all kinematics formulas for this situation

a(t) = (3 ft/s^4)*t^2
v(t) = (1ft/s^4) t^3 - 32 ft/sec
x(t) = (1/4 ft/s^4)*t^4 - (32 ft/sec)*t + 64 ft

Suppose that the equation of motion for a particle?

Suppose that the equation of motion for a particle (where s is in meters and t in seconds) is s= t^4-2t^3+8

a. Find the time where acceleration is zero (besides at t=0)
b.Find the position and velocity at this time

The acceleration of a particle is defined by the relation a= k t^2.?

a=kt² ; so v = ∫a.dt = ⅓.k.t³ + C₁and
s = ∫v.dt = k.t⁴/12 + C₁.t + C₂ ; Given s=24 at t=0 we get: C₂= 24
1. From the condition for s given in 1 we have: 96 = k.6⁴/12 + 6.C₁+ 24 or k.108 + 6.C₁= 72 .... (1)
From the condition for v given in 1 we have: 18 = 72.k + C₁= 18 giving C₁= 18-72.k
Substituting this into (1) gives 108.k + 6.(18-72.k) = 72 or 3k + 3 – 12.k = 2 so that k=1/9

2. Hence C₁= 10 giving v = t³/27 +10 which at t=2 gives v = 10.3 m/s

The equation of motion for a particle is given by s= 2t^3 - 9t^2 - 24t , t >_ 0?

a) Velocity is just the time-derivative of position.
s'(t) = 6t^2 - 18t - 24.

b) Acceleration is just the time-derivative of velocity (or the second time-derivative of position.)
s''(t) = 12t - 18.

c) s''t(1) = 12(1) - 18 = -6 meters/sec^2.

d) 6t^2 - 18t - 24 = 0
t^2 - 3t - 4 = 0.
(t - 4)(t + 1) = 0. Since we're just looking at t > o here, we want the t = 4 solution.
At t = 4, the acceleration is
s''t(4) = 12(4) - 48 = 0. The acceleration is 0.

A particle moves according to a law of motion s = f(t), t ≥ 0, where t is measured in seconds and s in feet.?

f(t) = t^3 − 6t^2 + 9t

(a) velocity @ time, t = v(t)
v(t) = f'(t)
Where f'(t) = 3*t^(3-1) - 6a2t^(2-1) + 9*1t^(1-1)
= 3t^2 - 12t^1 + 9t^0 [where a^0 = 1],
= 3t^2 - 12t + 9
= 3[t^2 - 4t + 3]
v(t) = 3[t^2 - 4t + 3]

b) v(2) = f'(2)
= 3 [ (2)^2 - 4(2) + 3 ]
= 3 [ 4 - 8 + 3 ]
= 3 [ -4 + 3 ]
= 3 [ -1 ] = -3
v(2) = -3 ft/s
[ Recall that velocity is rate of change of displacement with time and has magnitude, (3ft/s) and direction (-ve sign) ]
Hence,
v(2) = 3 ft/s in the negative direction.

c) @ rest, v = 0 ft/s
=> f'(t) = 0
3 [ t^2 - 4t + 3 ] = 0
Divide both sides by 3,
t^2 - 4t + 3 = 0
t^2 - 3t - t + 3 = 0
t(t - 3) - 1(t - 3) = 0
(t - 1)(t - 3) = 0
t - 1 = 0 and t - 3 = 0
t = 1, 3
[ t, v(t) ] = [1, 0], [3, 0]
Thus,
t = 1s, 3s

d) Positive direction = when v(t) > 0
= f'(t) > 0
3 [ t^2 - 4t + 3 ] > 0
5ivide both sides by 3,
t^2 - 4t + 3 > 0
t^2 - 3t - t + 3 > 0
t(t - 3) - 1(t - 3) > 0
(t - 1)(t - 3) > 0
t - 1 > 0 and t - 3 > 0
t > 1 and t > 3
t = { 1 < t < 3: t > 3 }

e) Total distance traveled during the first 4s = f(4)
f(t) = t^3 - 6t^2 + 9t
f(4) = (4)^3 - 6(4)^2 + 9(4)
= 64 - 6(16) + 36
= 64 - 96 + 36
= 64 - 60
= 4 ft
f(4) = 4ft

The equation of motion of a particle is s=2t^3-7t^2+4t+1 ?

s=2t^3-7t^2+4t+1

a)

velocity, v = ds/dt = 6t^2 - 14t + 4 = 2(3t^2 - 7t + 2) m/s

acceleration, a = dv/dt = 12t - 14 = 2(6t - 7) m/s^2

b)

a(1) = 12(1) - 14 = -2 m /s^2

The equation of motion of a particle is s = t3 − 3t, where s is in meters and t is in seconds. (Assume t ≥ 0?

s(t) = t^3 − 3t where t ≥ 0

a) velocity, v(t) = s'(t)
v(t) = 3*t^(3-1) - 3*1t^(1-1)
= 3t^2 - 3t^0
= 3t^2 - 3
v(t) = 3[t^2 - 1] [where t ≥ 0]

Acceleration, a(t) = v'(t) = s"(t)
Where v(t) = 3t^2 - 3
= 3*2t^(2-1) - 3*0t^(0-1)
= 6t - 0
= 6t
a(t) = 6t [where t ≥ 0]

b) accleration after 4s
= a(4)
a(4) = 6(4) = 24
a(4) = 24m/s^2

c) acceleration when velocity, v(t) = 0
When v(t) = 0 find t,
When v(t) = 0,
3[t^2 - 1] = 0
Divide both sides by 3,
t^2 - 1 = 0
t^2 = 1
t = ± √[ 1/2 ]
t = ± 1/√2 = ±(√2)/2 s
Since t ≥ 0,
t = +(√2)/2 s
t = (√2)/2 s
Now, find a(√2/2),
a(t) = 6t
a((√2)/2) = 6[(√2)/2]
= 6/2 [√2]
= 3√2 m/s^2

The Position of a particle is given by the Equation s=F(t)= t^3-6t^2=9t?

The Velocity is V=3t^2-12t+9

The question is:
How do you draw the diagram in motion? Which equation do I use?

How do you find the total distance traveled by the particle during the first 5 seconds

The acceleration of a particle, a m/s^2 moving in a straight line at time t seconds is given by a = t + 1. How do I find the formula for velocity and displacement given that s=0 and v=8 when t=0?

Acceleration is given by:[math]a=\dfrac{dv}{dt}\implies t+1=\dfrac{dv}{dt}\implies[/math] [math]dv= (t+1)dt[/math]Integrating both sides w.r.t. dt,[math]\int (t+1)dt=\int dv[/math][math]\dfrac{t^2}{2}+t+c=v... (1)[/math](c is the constant of integration when an indefinite integral is evaluated )According to the condition,at t=0,v=8.Substituting t=0,v=8 in (1),c=8.So the equation (1) becomes[math]v=\dfrac{t^2}{2}+t+8 ... (2)[/math]To obtain the expression for displacement,write v=ds/dt.Thus (2) can be written as:[math]\dfrac{ds}{dt}=\dfrac{t^2}{2}+t+8\implies ds=(\dfrac{t^2}{2}+t+8)dt[/math]Again Integrating both sides w.r.t dt,[math]\int ds=\int(\dfrac{t^2}{2}+t+8)dt[/math][math]s=\dfrac{t^3}{6}+\dfrac{t^2}{2}+8t+c... (3)[/math](c is the constant of integration )According to the condition at t=0,s=0.Putting t=0,s=0 in eqn (3)c=0.Thus eqn (3) becomes[math]s=\dfrac{t^3}{6}+\dfrac{t^2}{2}+8t[/math]This the equation for displacement.Hope it helps!!

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