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Physics Question

Era I Wilshere · 2014-09-21 17:35:17

A car moves along a road in such a way that the distance x, travelled in a time t, is given by x = a + bt 3 where a and b have the constant values. Derive an expression for the velocity, v, as a function of time. Express your answers in terms of v, b and t. Does anybody hav any idea how to do this question

21-09-2014 5:35pm

#1

Era I Wilshere

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A car moves along a road in such a way that the distance x, travelled in a time t, is
given by
x = a + bt 3

where a and b have the constant values.

Derive an expression for the velocity, v, as a function of time.
Express your answers in terms of v, b and t.

Does anybody hav any idea how to do this question

0

Comments

#2 21-09-2014 5:37pm

Era I Wilshere

Registered Users, Registered Users 2 Posts: 22 ✭

Join Date: July 2014

Posts: 16

sorry should be

x = a + bt^3

0
#3 21-09-2014 5:40pm

5uspect

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X is the position, t is time. The rate of change of position with time is the velocity. So differentiate the expression to get dx/dt.

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#4 21-09-2014 5:43pm

dlouth15

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You have an expression for position: x = a + bt^3 in terms of time t.

Velocity is the rate of change of position x with respect to time t.

How do you think you might go about finding the rate of change of position with respect to time in this case? What is the mathematical operation that finds the rate of change of something with respect to something else?

0