college Physics
posted by Katie .
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. Write expressions for the position vector, the velocity vector, and the acceleration vector of the object at any time t > 0. (Use the following variables as necessary: omega for ù and t.)
For the position vector I got:
7.16sin(omega*t)i+4.007.16cos(omega*t)j
For the velocity vector I got:
7.16*omega*cos(omega*t)i+7.16*omega*sin(omega*t)j
For the acceleration vecotr I got:
7.16*omega^2*sin(omega*ti)+7.16*omega^2*sin(omega*t)j
I this correct or not? My homework is computer based and when I type this in, it marks it wrong. Please help.

The only two things I see wrong is you have on acceleration the unit vector i inside the argument of the sin function, and on the lst part of the acceleration vector, you should have COSINE, not sine

One error
For the acceleration vector I got:
7.16*omega^2*sin(omega*ti)+7.16*omega^2*__________sin(omega*t)______j
should be
For the acceleration vector I got:
7.16*omega^2*sin(omega*ti)+7.16*omega^2*cos(omega*t)j
Note that
acceleration =  omega^2 *( sin and cos components of displacement)
Respond to this Question
Similar Questions

Trig
4. Asked to simplify the expression sin(180−è), Rory volunteered the following solution: sin(180−è) = sin 180−sin è, and, because sin 180 is zero, it follows that sin(180−è) is the same as −sin è. … 
calculus
Find an equation for the surface consisting of all points P(x, y, z) equidistant from the point P(0, 1, 0) and the plane x = 3. Answer Choices: 1. y2 + z2 − 6x + 2y − 8 = 0 2. x2 + z2 + 6y − 2z − 8 = 0 3. y2 … 
maths
Choose the option that gives an expression for the indefinite integral ʃ (cos(4x) + 2x^2)(sin(4x) − x) dx. In each option, c is an arbitrary constant. Options A cos(4x) + 2x^2 +c B 1/8cos(4x) + 2x^2)^2 +c C 1/4 (sin(4x) … 
Pre Calculus
Use one of the identities cos(t + 2ðk) = cos t or sin(t + 2ðk) = sin t to evaluate each expression. (Enter your answers in exact form.) (a) sin(17ð/4) (b) sin(−17ð/4) (c) cos(17ð) (d) cos(45ð/4) (e) tan(−3ð/4) (f) … 
Pre Calculus
Use one of the identities cos(t + 2ðk) = cos t or sin(t + 2ðk) = sin t to evaluate each expression. (Enter your answers in exact form.) (a) sin(17ð/4) (b) sin(−17ð/4) (c) cos(17ð) (d) cos(45ð/4) (e) tan(−3ð/4) (f) … 
physics
The coordinates of an object moving in the xy plane vary with time according to the equations x = −6.85 sin ùt and y = 4.00 − 6.85 cos ùt, where ù is a constant, x and y are in meters, and t is in seconds. (a) Determine … 
biology
Given the part of the molecule shown below, can the underlined atom participate in a hydrogen bond with an approriate bonding partner? 
physics
Four charges −8 × 10^−9 C at (0 m, 0 m), −7 × 10^−9 C at (5 m, 1 m), −1 × 10^−9 C at (−2 m, −3 m), and 2 × 10^−9 C at (−2 m, 4 m), are arranged in the (x, y) plane as … 
MATH
Solve the following equations for x where 0 ≤ x < 2π. tan(x)sin(2x) = √3 sin (x) and cos(2x)−cos(x) = −sin2(x)+1/4 Stuck on these particular types. Have no idea how to start. 
Quick calc question
Find the velocity, v(t), for an object moving along the xaxis if the acceleration, a(t), is a(t) = 2t + sin(t) and v(0) = 4. v(t) = t2 + cos(t) + 3 v(t) = 2 + cos(t) + 1< my answer v(t) = t2 − cos(t) + 5 v(t) = t2 + sin(t) …