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3 years ago

A particle's position along the x-axis is described by: x(t)=A t + B t2

Physics

1 answer:

ki77a [65]3 years ago

8 0

Answer:

a)V = 25.1 m/s

b)V = 4.226 m/s

Explanation:

Given that

x(t)=A t + B t²

A = -4.3 m/s

B = 4.9 m/s²

x(t)= - 4.3 t +4.9 t²

The velocity of the particle is given as

$V=\dfrac{dx}{dt}$

V=-4.3 + 4.9 x 2 t

V= - 4.3 + 9.8 t m/s

Velocity at point t= 3 s

V= - 4. 3 + 9.8 x 3 m/s

V= - 4.3 + 29 .4 m/s

V = 25.1 m/s

At origin :

x= 0 m

0 = - 4.3 t +4.9 t²

0 = - 4.3 + 4.9 t

$t=\dfrac{4.3}{4.9}\ s$

t=0.87 s

The velocity at t= 0.87 s

V= - 4.3 + 9.8 t m/s

V= - 4. 3 + 9.8 x 0.87 m/s

V= - 4.3 + 8.526 m/s

V = 4.226 m/s

a)V = 25.1 m/s

b)V = 4.226 m/s

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3 years ago

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Question isn’t clear
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3 years ago

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Answer:

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