Help With Physics Questions I just need help with how to do the set up equations

Question

Help With Physics Questions
I just need help with how to do the set up equations im so lost

1- You are traveling with a constant speed of 26 m/s. (a) What is this speed in units of mi/h? (b) How far
do you travel (in m) in a time of 27 min? Does this value seem reasonable? (c) What can you say about the
average speed during this time and the instantaneous speed at any instant during this time interval?

2-You travel east for 32 km at 22 m/s. You then travel west for 35 min at 30 m/s. Let the positive-x direction
point eastward, and say that you started at the position xi = 0. (a) What total distance did you travel during
your trip? (b) What was your final x-position? (c) What was your average speed during this trip? (d) What
was your average x-component of velocity?

Explanation / Answer

1).

a).
1 m/s = 2.237 mi/h

26 m/s = 2.237* 26 = 58.162 mi/h

b).
distance = speed*time = 26* (27*60) = 42120 m
Yes, this value is reasonable because it is just 42.12 km in 27 mins which one can travel if he is moving in some fast vehicle.

c).
Avg speed and instantaneous speed at any instant is same because the speed is constant throughout.

Avg. speed = instantaneous speed = 26 m/s

2).

a).
Total distance = 32000 + (30*35*60) = 95000 m = 95 km

b).
Final position = 32000 - (30*35*60) = -31000 m = -31 km

c).
Time taken while moving eastwards = distance/speed = 32000/22 = 1454.55 s = 0.404 hour

Avg. speed = total distance/total time = 95000/[(35*60)+(1454.55)] = 26.726 m/s

d).
Avg. x-component of velocity = total displacement/time taken = 31000/[(35*60)+(1454.55)] = 8.72 m/s

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