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Derek is riding his bike 10 mph. He takes 20 seconds to reach 15 mph. What is his acceleration?

0.25 mph/s


1.25 mph/s


4 mph/s


cannot be determined

User Shoshanah
by
6.7k points

2 Answers

3 votes

4 mph/s cause his change is 5mp in 20 seconds so do 20/5= 4 mph/s

User Toto Briac
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2 votes

Answer: The correct answer is 0.25 mph/s.

Step-by-step explanation:

The expression for the acceleration is as follows:


a= (v-u)/(t)

Here, a is the acceleration, v is the final velocity and u is the initial velocity.

It is given in the problem that Derek is riding his bike 10 mph. He takes 20 seconds to reach 15 mph.

Calculate the acceleration.

Put t= 20 s, v= 15 mph and u= 10 mph in the above expression.


a= (15-10)/(20)


a= 0.25 mph/s

Therefore, his acceleration is 0.25 mph/s.

User Urizen
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6.4k points