The position of a particle moving along the \(x\) -axis varies with time according to the expression \(x=4 t^{2},\) where \(x\) is in meters and \(t\) is in seconds. Evaluate the particle's position a) at \(t=2.00 \mathrm{~s}\). b) at \(2.00 \mathrm{~s}+\Delta t\) c) Evaluate the limit of \(\Delta x / \Delta t\) as \(\Delta t\) approaches zero, to find the velocity at \(t=2.00 \mathrm{~s}\).

Short Answer

Expert verified
Answer: The particle's position at t = 2.00 s is 16 meters, and its velocity at that time is 16 m/s.

Step by step solution

01

Part (a): Calculate the position at t = 2.00 s

To find the position of the particle at \(t = 2.00\) s, plug the value of \(t\) into the given expression for position \(x\): \(x = 4t^2\) \(x(2.00) = 4(2.00)^2\) \(x(2.00) = 4(4)\) \(x(2.00) = 16 \, \text{m}\) The particle's position at \(t = 2.00\) s is 16 meters.
02

Part (b): Calculate the position at t = 2.00 s + Δt

To find the position at \(t = 2.00 \, \text{s} + \Delta t\), plug this value of \(t\) into the position function: \(x(t) = 4t^2\) \(x(2.00+\Delta t) = 4(2.00+\Delta t)^2\) The position of the particle at \(t = 2.00\,\text{s} + \Delta t\) is \(x(2.00+\Delta t) = 4(2.00+\Delta t)^2\).
03

Part (c): Evaluate the limit of Δx/Δt to find the velocity at t = 2.00 s

To find the velocity of the particle at \(t = 2.00\) s, we need to find the limit of the difference quotient as \(\Delta t\) approaches zero: \(\lim_{\Delta t \to 0} \frac{x(2.00+\Delta t) - x(2.00)}{\Delta t}\) First, let's simplify the expression numerator: \(x(2.00+\Delta t) - x(2.00) = 4(2.00+\Delta t)^2 - 4(2.00)^2\) \(= 4[(2.00+\Delta t)^2 - (2.00)^2]\) Next, factor the difference of squares in the brackets: \(= 4[(2.00+\Delta t - 2.00)(2.00+\Delta t + 2.00)]\) \(= 4[\Delta t(4.00+\Delta t)]\) Now, let's put this back into our limit: \(\lim_{\Delta t \to 0} \frac{4[\Delta t(4.00+\Delta t)]}{\Delta t}\) We can cancel the \(\Delta t\) terms: \(\lim_{\Delta t \to 0} 4(4.00+\Delta t)\) Now, take the limit as \(\Delta t\) approaches zero: \(4(4.00 + 0)\) \(= 4(4.00)\) \(= 16 \, \mathrm{m/s}\) The particle's velocity at \(t = 2.00\) s is 16 m/s.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Consider three ice skaters: Anna moves in the positive \(x\) -direction without reversing. Bertha moves in the negative \(x\) -direction without reversing. Christine moves in the positive \(x\) -direction and then reverses the direction of her motion. For which of these skaters is the magnitude of the average velocity smaller than the average speed over some time interval?

The Bellagio Hotel in Las Vegas, Nevada, is well known for its Musical Fountains, which use 192 HyperShooters to fire water hundreds of feet into the air to the rhythm of music. One of the HyperShooters fires water straight upward to a height of \(240 \mathrm{ft}\). a) What is the initial speed of the water? b) What is the speed of the water when it is at half this height on its way down? c) How long will it take for the water to fall back to its original height from half its maximum height?

You and a friend are standing at the edge of a snowcovered cliff. At the same time, you both drop a snowball over the edge of the cliff. Your snowball is twice as heavy as your friend's. Neglect air resistance. (a) Which snowball will hit the ground first? (b) Which snowball will have the greater speed?

An object is thrown upward with a speed of \(28.0 \mathrm{~m} / \mathrm{s}\). What maximum height above the projection point does it reach?

A jet touches down on a runway with a speed of \(142.4 \mathrm{mph} .\) After \(12.4 \mathrm{~s},\) the jet comes to a complete stop. Assuming constant acceleration of the jet, how far down the runway from where it touched down does the jet stand?

See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free