The king gave them all fake seeds, the little girl was the only honest child who didn't switch seeds.
Answer:
Choice a.
, assuming that the skating rink is level.
Explanation:
<h3>Net force in the horizontal direction</h3>
There are two horizontal forces acting on the boy:
- The pull of his friend, and
- Frictions.
The boy should be moving in the direction of the pull of his friend. The frictions on this boy should oppose that motion. Therefore, the frictions on the boy would be in the opposite direction of the pull of his friend.
The net force in the horizontal direction should then be the difference between the pull of the friend, and the friction on this boy.
.
<h3>Net force in the vertical direction</h3>
The net force on this boy should be zero in the vertical direction. Consider Newton's Second Law of motion. The net force on an object is proportional to its acceleration. In this question, the net force on this boy in the vertical direction should be proportional to the vertical acceleration of this boy.
However, because (by assumption) the ice rink is level, the boy has no motion in the vertical direction. His vertical acceleration will be zero. As a result, the net force on him should also be zero in the vertical direction.
<h3>Net force</h3>
Therefore, the (combined) net force on this boy would be:
.
<span>change in velocity = final velocity - initial velocity = v - u
for comet:
uc = initial velocity of comet (before impact)
vc = final velocity of comet
mc= mass of comet
uc = 40000 kmph
vc = ?
mc= 10 x 10^14 kg
for probe:
up = initial velocity of probe (before impact)
vp = final velocity of probe
mp= mass of probe
up= 37000 kmph
vp= ?
mp= 372 kg
Now,
by principle of conservation of momentum
(mc x uc) - (mp x up) = (mc x vc) + (mp x vp)
Since probe is in comet after collision, vp= vc = V
then,
(mc x uc) - (mp x up) = V (mc + mp )
V = [(mc x uc) - (mp x up)] / (mc + mp )
= ((10 × 10^14 × 40000) - (372 × 37000)) ÷ ((10 × 10^14) + 372)
= ???
then,
change in velocity of the comet = ??? - (40000) =
</span>
When atmospheric pressure is higher than the absolute pressure of a gas in a container.