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3 years ago

1. A car accelerates uniformly from 12 m/s to 39 m/s in 12 seconds. What is the car's average acceleration

Physics

1 answer:

Alinara [238K]3 years ago

5 0

Answer:

(1) 2.25m/s^2

(2) 45.6m

Explanation:

(1) A car accelerates uniformly from 12m/s to 39m/s in 12 seconds

Therefore the average acceleration can be calculated as follows

a = 39-12/12

a = 27/12

a= 2.25m/s^2

(2) A butterfly is flying at 4m/s , it accelerates uniformly at 1.2 m/s for 6 seconds

u= 4

a= 1.2

t= 6

Therefore the distance can be calculated as follows

S= ut + 1/2at^2

= 4×6 + 1/2 × 1.2 × 6^2

= 24 + 1/2 × 1.2 × 36

= 24 + 1/2 × 43.2

= 24 + 21.6

S = 45.6m

Hence the butterfly travels at 45.6m

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