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
Hence, this is the required solution.
Answer:
F1= 588 N
F2= 784 N
Explanation:
Please see the attached file.
When you jumó ur legs put force on ground
Answer: The minimum time between pulses (in fresh water)
= 0.3106 s
Explanation:
To calculate the speed of echoes sounds, we will use
Speed = 2x/t
Where x = distance and t = total time.
Please note that:
sound travels at 343 m/s in air. But it travels at 1,481 m/s in water (almost 4.3 times as fast as in air);
Total distance = 2 × 230 = 460m
Using speed of sound in water
1481 = 460/t
t = 460/1481
t = 0.3106
