Physics

Problem

A car increases its velocity uniformly from

10\,\text{m/s}

30\,\text{m/s}

in the first

5\,\text{s}

and then keeps moving with this speed for the next

5\,\text{s}

. Which one of the following statements is correct? a) The average acceleration during the entire

10\,\text{s}

4\,\text{m/s}^2

and the instantaneous acceleration at

t = 7\,\text{s}

0\,\text{m/s}^2

. b) The average acceleration during the entire

10\,\text{s}

2\,\text{m/s}^2

and the instantaneous acceleration at

t = 7\,\text{s}

2\,\text{m/s}^2

. c) The average acceleration during the entire

10\,\text{s}

2\,\text{m/s}^2

and the instantaneous acceleration at

t = 7\,\text{s}

0\,\text{m/s}^2

. d) The average acceleration during the entire

10\,\text{s}

4\,\text{m/s}^2

and the instantaneous acceleration at

t = 3\,\text{s}

4\,\text{m/s}^2