The time taken to complete her run is 1.9 hr.
<u>Explanation:</u>
Speed is a scalar quantity and it is defined as the ratio of distance covered to the time taken to cover that distance. As distance is also a scalar quantity, so the directions given in the problem can be ignored. Thus, the distance covered by the jogger is the sum of kilometers given in problem.
Distance covered = 6+5+4 = 15 km
And the speed is given as 8 km/hr.
So the time taken will be ratio of distance to speed.
So the jogger will take 1.9 hr to complete her run.
Answer: c) Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.
Hey
On Earth, you can move or you can not move. if you are moving 50 mph that means relative to Earth (not the Andromeda galaxy). When you start moving (accelerating) you are now moving relative to Earth. when you start slowing down (decelerating [most scientists just say you have negative acceleration]) you are starting to match your velocity to Earth's velocity.
Hope it helped and made any sence at all.
Spiky bob your answerer.
The car traverses a distance 
after time 
according to
where 
is its acceleration, 10 m/s^2. The time it takes for the car to travel 25 m is
5 is pretty close to 4, so we can approximate the square root of 5 by 2. Then the car's velocity 
after 2 s of travel is given by
which makes C the most likely answer.
Answer:
233.1 miles per hours
Explanation:
Speed: This is defined as the ratio of distance to time. The S.I unit of speed is m/s. speed is a vector quantity because it can only be represented by magnitude only. Mathematically, speed can be expressed as,
S = d/t ....................... Equation 1
Where S = speed of the runner, d = distance covered, t = time.
Given: d = 100 meter , t = 9.580 seconds
Conversion:
If, 1 meter = 0.00062 miles
Then, 100 meters = (0.00062×100) miles = 0.62 miles.
Also
If, 3600 s = 1 h
Then, 9.580 s = (1×9.580)/3600 = 0.00266 hours.
Substitute into equation 1
S = 0.62/0.00266
S = 233.1 miles per hours.
Hence the runner speed is 233.1 miles per hours
