When does the speed equal 10 m/s?

Thread starter InsTanCeZ
Start date Jan 18, 2012
Tags

Vector Velocity

AI Thread Summary

The velocity of a particle in the xy plane is defined as v = (6.0t - 4.0t²) i + 6.0 j. To find when the speed equals 10 m/s, the magnitude of the velocity vector must be calculated. The equation for speed involves the components of the velocity, leading to the equation 6 - 8t = -10. Solving for t gives t = 2 seconds, but this solution is questioned as potentially incorrect. The discussion emphasizes the need to properly define speed in relation to vector velocity.

Jan 18, 2012

InsTanCeZ

Homework Statement

The velocity v of a particle moving in the xy plane is given by v = (6.0t - 4.0t2) i + 6.0 j, with v in meters per second and t (> 0) is in seconds.

(d) When does the speed equal 10 m/s?

Homework Equations

The Attempt at a Solution

6-8t=-10
t=2s
That's not right

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Jan 18, 2012

Clever-Name

Well, how is the speed defined in terms of the vector velocity

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