Question

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

Answer 1

Correct Answer - b
`v_(x)=5-4t, v_(y)=10`
`a_(x)=-4, a_(y)=0`
`veca=a_(x)hati+a_(y)hatj`
`veca=-4hatim//s^(2)`