The way I look at these things is like this:
-- The runner covered 12 meters in 4 seconds.
Average speed = 3 meters per second.
-- Speed at the beginning = zero.
In order to make the average 3, Speed at the end = 6 meters per second.
-- Speed increased from zero to 6 meters per second in 4 seconds.
It must have increased 1.5 meters per second each second.
That's choice-#2.
Hope this provides some answers
The total oxygen atoms that are exprected in the vinegar and baking soda reaction is three oxygen atoms.
Answer: B. 3
why;live
We have 365 days in a year because that is the approximate time of the world revolving around the sun once. It takes 365.25 days to go around once, but the calendar is 365, so we add leap years to add a couple more days.
Answer:
Force will be acting southward and the magnitude of force will be 1000 N
Explanation:
given,
mass of car = 1000 Kg
initial speed of the car (u) = 20 m/s
final speed of the car (v) = 0 m/s
distance to stop the car = 200 m
using equation of motion
v² = u² + 2 a s
0 = 20² + 2 x a x 200
400 a = -400
a = -1 m/s²
Now, we know
Force = mass x acceleration
F = 1000 x -1
F = -1000 N
- ve sign of force represent force will be acting in the opposite direction of motion.
Force will be acting southward and the magnitude of force will be 1000 N
