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3 years ago

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A person takes a trip, driving with a constant speed of 89.5 km/h, except for a 22.0-min rest stop. If the person’s average spee

d is 77.8 km/h, (a) how much time is spent on the trip and (b) how far does the person travel?

1 answer:

DanielleElmas [232]3 years ago

7 0

Answer:

(a): It spends on the trip 2.75 hr (2 hours 45 minutes)

(b): The person travels 213.9 km.

Explanation:

Vp= 77.8 km/h

V1= 89.5 km/h

V2= 0 km/h

t2= 0.36hr

t1= ?

Vp= (V1*t1 + V2*t2) / (t1 + t2)

clearing t1:

t1= 2.39 hr

Trip time= t1+t2

Trip time= 2.75 hr (a)

Distance traveled= V1*t1

Distace traveled= 213.9 km (b)

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Answer:

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From the question we are told that

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Generally the net force is given to be $FC(force towards center)$

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3 years ago

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svetlana [45]

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$\omega=-\alpha t$

$\alpha=-\dfrac{\omega}{t}$

$\alpha=-\dfrac{50.0}{20.0}$

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The angular acceleration is -2.5 rad/s²

We need to calculate the number of revolution

Using angular equation of motion

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Put the value into the formula

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Using formula of torque

$\vec{\tau}=\vec{r}\times\vec{f}$

$\tau=r\times f\sin\theta$

Put the value into the formula

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