Answer:
Options A, B, and C are all possible.
Explanation:
We know that the instantaneous velocity of the dog at 3:14PM is possitive to toward the flowers. But what about the acceleration to toward the flowers?
If the dog is decreasing speed at 3:14PM, it means that acceleration is negative toward the flowers, hence (since F=ma) the net force points away from the flowers.
If the dog is increasing speed at 3:14PM, it means that acceleration is positive toward the flowers, hence (since F=ma) the net force points toward the flowers.
If the dog is not increasing nor decreasing speed at 3:14PM, it means that acceleration is 0, hence (since F=ma) the net force is null and it does not point neighter to toward the flowers nor away from the flowers. This happens when the forces acting on the dog are equal to both sides.
Answer:
2940.1 joules would you burn in climbing stairs all day.
Explanation:
Work = W = F
d
going up stairs would be against force of gravity
W = mgh
where h is the height
the question is not complete because we need speed or distance
h = v
t
so assuming 1 step per second
h = 86,400 steps
7inchs/step
0.0254 m/inch
h = 15362 m
so from this
W = 800 N
15362
= 12289600 J
that means YOU need 12289600 J to walk 1 step per second all day
divide that by 4180 J /Kcal
Kcal = ![\frac{W}{(J/Kcal)}](https://tex.z-dn.net/?f=%5Cfrac%7BW%7D%7B%28J%2FKcal%29%7D)
= ![\frac{12289600}{4180}](https://tex.z-dn.net/?f=%5Cfrac%7B12289600%7D%7B4180%7D)
= 2940.1 Kcal
if you ran faster you would use more energy 2 steps per second would mean 5880 Kcal.
The surface of the water or himself
Acceleration = (change in speed) / (time for the change)
Change in speed = (ending speed) - (starting speed)
Change in speed = (25 m/s) - (5 m/s) = 20 m/s
Time for the change = 20 sec
Acceleration = (20 m/s) / (20 sec)
<em>Acceleration = 1 m/s²</em>