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3 years ago

1. A student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag.

Physics

1 answer:

Snezhnost [94]3 years ago

8 0

Explanation:

(a) Displacement of an object is the shortest path covered by it.

In this problem, a student is biking to school. She travels 0.7 km north, then realizes something has fallen out of her bag. She travels 0.3 km south to retrieve her item. She then travels 0.4 mi north to arrive at school.

0.4 miles = 0.64 km

displacement = 0.7-0.3+0.64 = 1.04 km

(b) Average velocity = total displacement/total time

t = 15 min = 0.25 hour

$v=\dfrac{1.04\ km}{0.25\ h}\\\\v=4.16\ km/h$

Hence, this is the required solution.

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3 years ago

An ice boat is coasting along a frozen lake. Friction between the ice and the boat is negligible, and so is air resistance. Noth

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