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Description
In classical mechanics, impulse is the integral of a force, F, over the time interval, t, for which it acts. Since force is a vector quantity, impulse is also a vector quantity. Impulse applied to an object produces an equivalent vector change in its linear momentum, also in the resultant direction.
A it sinks the submarine because of the water that is going into the submarine
Here is the first question
Answer:
Car A is 1.8-1.2= 0.6 times faster than car B
So the distance between them is changing 0.6 times faster.
Explanation:
Car A is traveling north at 90km/hr and 0.3 km away from intersection point.
Car b is traveling west at 80km/hr and 0.4 km away from the intersection point.
The time it will take to get to intersection point by those two cars is how fast it is changing.
For car A
Time = distance/speed
Time = 0.3/90
Time = 3.333*10^-3
Time = 3.333*10^-3 hrs
Converting to seconds
(3.333*10^-3)*360= 1.199998
Approximately 1.2 seconds
For car B
Time = distance/time
Time= 0.4/80
Time = 5*10^-3
Time= 5*10^-3 hrs
Converting to seconds
(5*10^-3)*360= 1.8 seconds
Comparing the two times,
Car A is 1.8-1.2= 0.6 times faster than car B
Power = (work done) / (time to do the work)
Work done = (force) x (distance)
Force = (weight of the crate) = (mass of the crate) x (gravity)
Crate weight = (100 kg) x (9.8 m/s²)
Force = 980 Newtons
Work done = (980 N) x (2 m) = 1,960 Joules
Power = (1,960 Joules) / (4 seconds)
<em>Power = 490 Joules per second</em>
(Whoever wrote the question used 10 m/s² for gravity instead of 9.8 m/s², so his answer came out to be 500 W. That's <em>choice-B</em> .)
<em>Power = 490 watts</em>