Question

please give me answers of these questions
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Answer 1

Q.9) Initial velocity (u)=30 m/s

Final velocity (v)=40 m/s

Time taken (t)= 2 s

So, acceleration (a)=v-u/t

=40-30/2

=10/2

=5

So, acceleration produced=5 m/s²

Q.10) Initial velocity (u)=20 m/s

As its speed decreases, so it comes to rest after some time.

So, Final velocity (v)=0 m/s

Acceleration (a)=0.4 m/s²

Time taken=t

So, a=v-u/t

0.4=0-20/t

0.4t=-20

t=-20/0.4

t=50

So, time taken=50 s