Answer:
Distance will be 49.34 m
Explanation:
We have given wavelength 
Diameter of the antenna d = 2.7 m
Range L = 7.8 km = 7800 m
We have to find the smallest distance hat two speedboats can be from each other and still be resolved as two separate objects D
We know that distance is given by 
So distance D will be 49.34 m
The impulse is (force) x (time) = (20 N) x (20 sec) = 400 N-sec
When we grind through the units, we find that the [newton-second]
is exactly the same as the [kilogram-meter/sec] unit-wise, and once
we know that, it doesn't surprise us to learn that impulse is equivalent
to a change in momentum (mass x speed ... also kg-m/s).
So this impulse exerted on the moving object adds 400 kg-m/s of
linear momentum to its motion, directed to the right. That may or
may not be the total change in its momentum during that 20-sec,
because our 20-N may not be the only force acting on it.
It would take more energy to reheat 12 cups because only 1 or 2 cups can fit in a microwave rather an than brewing 12 cups in a coffee pot.
Answer:
Explanation:
Total distance covered = 25 + 15 = 40 m
Total time = 15 + 8 = 23 s
Average speed = total distance covered / total time
= 40 / 23
= 1.74 m / s
Total displacement = 25 - 15 = 10 m
Total time = 15 + 8 = 23 s
Average velocity = total displacement / total time
= 10 / 23
= .434 m / s to the right .
