Answer:
Choice A: approximately 
, assuming that the two pistons are connected via some confined liquid to form a simple machine.
Explanation:
Assume that the two pistons are connected via some liquid that is confined. Pressure from the first piston:
.
By Pascal's Principle, because the first piston exerted a pressure of 
on the liquid, the liquid will now exert the same amount of pressure on the walls of the container.
Assume that the second piston is part of that wall. The pressure on the second piston will also be . In other words:
.
To achieve a force of 
, the surface area of the second piston should be:
.
I believe it is the first one
Answer:
The World Series
Explanation:
The Super Bowl is the championship American Football game, and the World Cup is the Soccer/Football game.
American Football and Football are different things. The first is what Americans call football, while the other is what Americans call soccer. It is confusing.
V=at and a=F/m
140/.070 = 2000m/s^2
2000*.020 = 40m/s
The ball’s velocity increased by 40m/s.
Answer:
The correct option is C
Explanation:
According to third equation of motion, v
2
=u
2
+2ax
Here, u=0 m/s
a=−g and x=−h
Negative sign indicates downward direction. Displacement and acceleration both are downwards.
So,v=±
2(−g)(−h)
We take minus sign because it is downwards.
v=−
2gh
After bouncing. velocity becomes 80% of v, i.e.,
v
′
=+0.8
2gh
(positive sign because the direction of ball has reversed after bouncing and is upwards.
Applying third equation of motion again, for u=v
′
, v=0 and a=−g
v
2
=u
2
+2×a×x
Thus,
0=0.64(2gh)+2(−g)x
or
x=0.64h
