8. during the last few kilometers of a marathon, runners play mental games to test each
other out. they accelerate to see if the other runners will accelerate also. if a runner
has a velocity of 5 m/s and accelerates to 5.2 m/s after covering 10 m, calculate the
runner's average acceleration.

The runner's average acceleration is 0.102 m/s²

Explanation:

The runner accelerates from 5 m/s to 5.2 m/s and covering 10 m

We need to find the runner's average acceleration

The given is:

→ Initial velocity 5 m/s

→ Final velocity 5.2 m/s

→ Distance 10 meters

→ Acceleration ?

We need a suitable rule for the given

→ v² = u² + 2 a s

where v is the final velocity, u is the initial velocity, a is the acceleration

and s is the distance

Substitute the values above in the rule

→ (5.2)² = (5)² + 2 a (10)

→ 27.04 = 25 + 20 a

Subtract 25 from both sides

→2.04 = 20 a

Divide both sides by 20

→ a = 0.102 m/s²

The runner's average acceleration is 0.102 m/s²

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when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27