Chapter 3.6, Problem 15P

To determine

To Find: The value of $v_0$ and $a$ if $v=v_0+at$

Answer to Problem 15P

The answer is $v_0=8$ and $a=5$ .

Explanation of Solution

Given Information: It is given that the speed of the particle after time t is related to intial speed $v_0$ and constant acceleration $a$ by

  $v=v_0+at$  (1)

Calculation:

It is given that

  $v_0=8$

  $v=28$ when $t=4$

Putting the above values in (1),

  $28=v_0+4a$  (2)

Now, $v=43$ when $t=7$

Putting the above values in (1),

  $43=v_0+7a$  (3)

Now subtract (2) from (3) to have

  $3a=15$

  $a=5$

Put this value of ain (2), to find $v_0$

So,

  $v_0+20=28$

  $v_0=8$

Thus, $v_0=8$ and $a=5$ .