# Physics

posted by .

Uniform Circular Motion:

Suppose that a particle's position is given by the following expression:

r(t) = Rcos(omega*t)i + Rsin(omega*t)j

1. Choose the answer that best completes the following sentence:
The particle's motion at t=0 can be described by ____________.

a. an ellipse starting at time t=0 on the positive x axis
b. an ellipse starting at time t=0 on the positive y axis
c. a circle starting at time t=0 on the positive x axis
d. a circle starting at time t=0 on the positive y axis

2. When does the particle first cross the negative x axis?
Express your answer in terms of some or all of the variables omega, R, and pi.

3. Find the particle's velocity as a function of time.
Express your answer using unit vectors (e.g., A i+ B j, where A and B are functions of omega, R, t, and pi).

4. Find the speed of the particle at time t.
Express your answer in terms of some or all of the variables omega, R, and pi.

• Physics -

I will be happy to critique your thoughts. One comment: What is this x,y axis talk, the equation uses i,j axis.

• Physics -

it is the function r(t).

• Physics -

2. pi/w
3. -wRsin(wt)ihat +wRcos(wt)jhat
4.R*w

• Physics -

1. a circle starting at time on the positive x axis

• Physics -

1.
circle on x axis

## Similar Questions

1. ### Physics

To find the velocity and acceleration vectors for uniform circular motion and to recognize that this acceleration is the centripetal acceleration. Suppose that a particle's position is given by the following expression: r(t) = Rcos(omega*t)i …
2. ### physics

For this problem use the Uniform circular motion mode of the simulation. (a) Given the limits on the sliders in the simulation, what is the maximum possible speed that can be achieved in "Uniform circular motion" mode?
3. ### college Physics

The coordinates of an object moving in the xy plane vary with time according to the following equations x = −7.16 sin ùt and y = 4.00 − 7.16 cos ùt, where ù is a constant, x and y are in meters, and t is in seconds. …
4. ### physics

Two particles A and B are in uniform circular motion about a common center. The acceleration of particle A is 4.7 times that of particle B. Particle B takes 2.4 times as long for a rotation as particle A. Th ratio of the radius of …
5. ### Physics

A charged particle is projected into a uniform B-field. Its velocity vector is perpendicular to the B-field vector. What type of path will the particle travel?
6. ### science

An object moves up and down the y-axis with an acceleration given as a function of time t by the expression a equals A sine of omega-t. , whereA. and omega. are constants. What is the period of this motion?
7. ### Calculus

The position function of a particle in rectilinear motion is given by s(t) s(t) = t^3 - 9t^2 + 24t + 1 for t ≥ 0. Find the position and acceleration of the particle at the instant the when the particle reverses direction. Include …
8. ### Harmonic Motion

we know that a particle in Harmonic Motion is moving at v1 @ position x1 and v2 @ position x2. What is A (Amplitude) and w (omega) ?
9. ### Calculus

The position function of a particle in rectilinear motion is given by s(t) = 2t^3 – 21t^2 + 60t + 3 for t ≥ 0. Find the position and acceleration of the particle at the instant the when the particle reverses direction. Include …
10. ### precalculus, complex numbers

Let $\omega$ be a complex number such that $\omega^7 = 1$ and $\omega \neq 1$. Let $\alpha = \omega + \omega^2 + \omega^4$ and $\beta = \omega^3 + \omega^5 + \omega^6$. Then $\alpha$ and $\beta$ are roots of the quadratic \[x^2 + px …

More Similar Questions