The x and y coordinates of the particle at any time are `x=5t-2t^(2) and y=10t` respectively, where x and y are in meters and t in seconds. The acceleration of the particle at t=2s is:

Options

A. 0
B. `5m//s^(2)`
C. `-4 m//s^(2)`
D. `-8m//s^(2)`

Answer

C

Explanation

The component of velocity along X axis.
`v_(x)=(dx)/(dt)=5-4tm//s`
The component of velocity along Y-axis.
`v_(x)=(dy)/(dt)=10m//s`
Acceleration of the particle along the X axis,
`a_(x)=(dv_(x))/(dt)=-4m//s^(2)`
Acceleratio of the particle along the Y-axis,
`a_(y)=(dv_(y))/(dt)=0`
The net acceleration of the particle is `-4m//s^(2)` and it remains same.